Bakery style pumpkin chocolate chip muffins with tall domed tops, deep spice from blooming it in the butter, and mini chocolate chips in every single bite.
Melt the butter and stir in the oil. Whisk the pumpkin pie spice into the warm fat and let it sit 1 minute. This is where the flavor comes from, so do not skip it.
½ cup butter, 1 tbsp pumpkin pie spice, 2 tbsp neutral oil
To a large bowl, add the bloomed butter and oil, both sugars, the pumpkin puree, eggs, Greek yogurt, and vanilla.
½ cup granulated sugar, ¾ cup dark brown sugar, 1½ cups pumpkin puree, 2 large eggs, ½ cup full-fat Greek yogurt, 1 tbsp vanilla extract
Whisk until completely smooth and uniformly orange, with no streaks of yogurt or egg.
In a separate bowl, whisk the flour, baking powder, baking soda, and salt. Tip it all onto the wet mixture and fold with a rubber spatula just until the dry flour disappears. A few lumps are fine and better than overmixing.
2 cups all purpose flour, 2 tsp baking powder, ¾ tsp baking soda, ¾ tsp salt
Scatter the mini and regular chocolate chips over the batter and gently fold to mix them evenly. Don't overmix.
¾ cup mini semi sweet chocolate chips, ¼ cup regular chocolate chips
Let the batter rest 20 minutes at room temperature, and preheat your oven to 425F while it rests. The rest lets the flour hydrate so the batter thickens and holds a dome, and your oven needs that time anyway.
Line two 12-cup muffin pans with 6 paper liners each, staggering them so no two liners sit next to each other. Divide the batter between all 12, filling each liner right up to the rim, about 121 g per cup. This is the step that decides whether you get bakery tops, so do not go light. Press a few extra chips into the tops.
Bake at 425F for 5 minutes. Then reduce the oven to 350F without opening the door and bake 14 to 17 minutes more.
The muffins are done at 200F-205F in the center. Check with an instant-read thermometer rather than going by the tops. or insert a wooden skewer in the center and make sure it comes out without wet batter.
Cool in the pans 5 minutes only, then transfer to a wire rack.
Notes
Bloom the spice. A minute in hot melted butter roughly doubles how much spice you taste, because those aromatics dissolve in fat and not in water. It is the difference between a pumpkin muffin and a brown muffin.Why two pans. Six liners per pan with an empty well beside each one lets hot air wrap all the way around every muffin. If you only have one pan, bake six staggered and then the second six. The second batch will dome slightly less.The temperature drop is the whole recipe. That first blast at 425F sets the outside fast so the inside has nowhere to go but up. Opening the door during the switch drops your oven temperature and you lose the dome.Greek yogurt swap. Full fat sour cream works exactly the same way.Storing. Airtight at room temperature up to 3 days, best on day one. Freeze cooled muffins up to 3 months and warm from frozen at 300F for about 10 minutes.