Adapted from Annie’s Eats
1 cup milk
Preheat oven to 350°F. Line two 12-cup muffin tins with cupcake liners.
Heat milk and butter in a small saucepan over medium heat until butter melts. Remove from heat. In a medium bowl, whisk together flour, baking powder, cinnamon and salt.
Using a stand mixer with a whisk attachment, beat eggs and sugar until thick ribbons form, about 5 minutes. Add flour mixture and beat on low just until incorporated. Add milk mixture and vanilla, and beat until blended.
Divide evenly among baking tins. Bake at 350°F for 16-18 minutes, or until a toothpick comes out clean. Cool in pans for 5 minutes, then transfer to wire racks to cool completely.