Ingredients

• 1 and 2/3 cups (200g) cake flour (spoon & leveled)
• 2 tbls flour
• 1 teaspoon baking powder
• 1/2 teaspoon baking soda
• 1/4 teaspoon salt
• 1/3 cup oil
• 1/2 cup (115g) unsalted butter, softened to room temperature
• 1 cup (200g) granulated sugar
• 2 egg
• 1 egg whites, at room temperature
• 1 and 1/2 teaspoons pure vanilla extract
• 1/4 cup sour cream
• 1/3 cup (80ml) buttermilk
• 1/3 cup reduced strawberry puree (see note)*

Directions

1. Make the reduced strawberry puree and allow it to cool completely. See note for instruction.
2. Preheat the oven to 350°F (177°C). Line a 12-cup muffin pan with cupcake liners. Line a second pan with 2-3 liners – this recipe makes 14-15 cupcakes. Set aside.
3. Whisk the cake flour, baking powder, baking soda, and salt together. Set aside.
4. Using a handheld or stand mixer fitted with a whisk attachment, beat the butter, oil and sugar together on high speed until smooth and creamed, about 2 minutes. Scrape down the sides and up the bottom of the bowl with a rubber spatula as needed. Beat in the egg and egg whites on high speed until combined, about 2 minutes. Add vanilla extract. Scrape down the sides and up the bottom of the bowl as needed. With the mixer on low speed, add the dry ingredients until just incorporated. Mix buttermilk and sour cream together and with the mixer still running on low, slowly pour mixture *just* until combined. Do not overmix. Whisk in 1/3 cup of reduced strawberry puree, making sure there are no lumps at the bottom of the bowl. Batter will be slightly thick.
5. Pour/spoon the batter into the liners. Fill only 2/3 full to avoid baking over the sides. Bake for 20-22 minutes, or until a toothpick inserted in the center comes out clean. For around 35 mini cupcakes, bake for about 11-13 minutes, same oven temperature.

Notes: 1/30/23 - I added 1/4 sour cream to recipe, but haven't tried making them since I added it. The last time I made them I used 2 eggs and 1 egg white, they were pretty good and moist. Next time I will try with sour cream and recipe as it is written above. 

3/9/23 - Made cupcakes as written in recipe and they were light, fluffy and moist! Very good. The cupcakes did sink slightly in the middle as they cooled. Maybe try adding a 1/4 tsp more baking soda next time.