Giant Costco-Copycat Gluten Free Banana Chocolate Chip Muffins

These muffins are DAMN good. They disappear nearly as fast as they come together, so making a second batch is highly recommended. My boyfriend absolutely adores banana chocolate chip bread, so these GIANT gluten free banana chocolate chip muffins are (I believe) his favorite of our giant muffins so far. Plus, they’re ridiculously-easy to make and they freeze really well, making these perfect weekday breakfast treats or emergency tough-day snacks that you simply pop in the microwave for instant, fluffy, studded-with-melty-chocolate-chips muffins! Plus, potassium! So there you go, they’re “healthy” too! For those of you just joining the giant muffin train, welcome aboard! This series of breakfasty/snacky treats started a few months back when I had the hankering for those giant Costco muffins that we used to get as kids (SO cheap and so good!), but, alas, Costco only makes them full of gluten so I hadn’t eaten one for 17 years. That is until I got myself some giant muffin pans (not a standard “jumbo” muffin tin, those actually aren’t that big – read on for the right pan size), and started making them myself! Thee flavors have now gone far beyond the Costco repertoire, as we’ve realized that this medium affords great creativity and variation on flavor and add-ins!

So far we’ve made these giant poppyseed muffins, giant blueberry muffins, giant chocolate chip muffins, giant double chocolate muffins, giant banana nut muffins, giant strawberry rhubarb muffins, giant apple streusel muffins, these giant lemon raspberry muffins, giant cherry chocolate chip muffins, giant coffee walnut muffins, and giant blackberry nectarine streusel muffins!

Tips for Fantastic Giant Muffins

A few tips for getting these to turn out just like you remember those Costco muffins:

• Use the right-size of pan! Apparently, Costco keeps their giant muffin pans as a trade secret because we can’t find them ANYWHERE on the internet and you can find EVERYTHING on the internet. Bravo, Costco, for a secret well-kept. However, we’ve found a way to crack the code and gone ahead and just used these brilliant 4-inch cake pans because, after careful inspection, we’ve discovered that Costco muffins are exactly 4-inches in diameter! HA! Take that, Costco-bakery-lords. I never thought I’d be regularly using 4-inch cake pans but here we are. I’ll just need to make a bunch of tiny cake recipes next!
• Let your batter REST, per the recipe, for at least 30 minutes. For two reasons: 1) the batter thickens as it rests which is incredibly important for a muffin filled with chunks of things like chocolate chips! A thicker batter will help suspend all of the stuff you’ve added all throughout your muffins, ensuring every bite has the perfect ratio of fluffy muffin to add-ins; and 2) something somewhere said that baking powder needs a bit more time to “activate.” Don’t quote me on this, who knows if it’s actually true.
• Don’t over-mix your batter! Muffins need a lot of lift, especially these giant ones, and if you over-mix your batter, you’ll end up with flat or sunken muffins which is no fun.
• Use a good 1-1 gluten free flour mix! We use the Bob’s Red Mill one (the baking mix), though we’ve heard good things about Cup-4-Cup. We’ve only tested this recipe with this one so if you want them to turn out exactly like ours, we recommend snagging a bag of that specific 1-1 gluten free flour.
• Use ripe, or even slightly under-ripe bananas! These banana muffins have a fluffy texture and a full banana flavor, so using super-ripe/brown/spotty bananas is NOT recommended. That’ll give you a totally different texture, will make them sweeter, and the flavor will change.
• Do NOT open the oven door during baking time. Tape it shut if you have to! You can certainly turn on the oven light and peek and the gloriousness that is a set of rising muffins nearly-ready to be devoured, but do not open that door! Opening the door will immediately lower the oven temp and prohibit your muffins from rising correctly. If you’re in the last few minutes of baking and need to test to see if they’re done, open the oven just a tiny bit and reach in and just tap the top of one – if it springs back it’s done, if it presses in like a foam mattress topper, it’s not and needs a couple more minutes!
• These will keep in an airtight container (or in ziplock baggies) for a week or so – and they freeze REALLY well! So if you want to make a batch and save a bunch, put them in a sturdy plastic container or a freezer plastic bag and pop them in there. Then microwave for about 30-45 seconds (from frozen) before eating! I even like popping mine in the microwave for 10-15 seconds from room temp to get them all warm and floofy again before eating.

Print Recipe

4.50 from 2 votes

Giant Costco Copycat Gluten Free Banana Chocolate Chip Muffins

These giant muffins are packed with banana and melty chocolate chips for the perfect, fluffy treat!

Prep Time20 minutes mins

Cook Time35 minutes mins

Resting time30 minutes mins

Course: Breakfast, Snack

Cuisine: American

Diet: Gluten Free

Keyword: banana, breakfast, chocolate chip, chocolate chip banana bread, costco muffins, easy, giant, gluten free, muffins, simple

Servings: 6 giant muffins

Calories: 500kcal

Author: Amelia Farber

Equipment

• Six 4-inch round cake pans (link below for the ones we use)
• Cookie sheet

Ingredients

• 4 medium, yellow bananas (about 500 grams) no brown spots!
• 3 large eggs
• 1 3/4 Cups white sugar
• 3/4 Cup melted salted butter
• 1/2 Cup sour cream
• 3 tsp vanilla extract
• 1/4 Cup milk
• 2 1/2 Cups gluten free 1-1 flour mix with xanthan gum added (if it doesn't have xanthan gum, add 1 teaspoon xanthan gum)
• 1/2 Cup packed blanched almond flour
• 2 3/4 tsp baking powder
• 3/4 tsp salt
• 1/8 tsp ground nutmeg
• 1 1/2 Cups semi-sweet chocolate chips

Instructions

• First, make the muffin batter! It will need to rest at room temp for 30 minutes before baking. In a large bowl, mash the bananas until smooth and there are very few lumps. Then whisk in the eggs, sugar, butter, milk, sour cream, and vanilla extract until thicker and smooth. Add in the gluten free 1-1 flour, packed blanched almond flour, baking powder, nutmeg and salt and whisk until totally combined and smooth. Then fold in the chocolate chips and then let the batter sit either on the counter for at least 30 minutes before baking (you can let it rest in the fridge for longer if you want).
• Once the batter has rested preheat the oven to 425° Fahrenheit and place your six 4-inch cake pans on a cookie sheet. Spray each pan with cooking spray, then spoon batter into each one evenly (they should be about 3/4-5/6 full) and then top each muffin with a generous amount of the crumble topping – completely covering each muffin. Bake for 5 minutes at 425 then immediately lower the temp to 350° F (do NOT open the oven door!) and let bake for 35-40 more minutes until the tops spring back with touched. Let cool nearly-completely before turning out!
• You can keep the muffins in zip-top bags or an airtight container in the fridge or freezer for up to a week. Best-served slightly warm, so pop them in the microwave for 10-20 seconds from room temp!

Tag @sisterssansgluten on Instagram if you snap a photo of your muffins!

Food photography and styling by Amelia Farber