01 -
Preheat your oven to 350°F. Grab a 9x13 dish and coat it with some nonstick spray.
02 -
Blend together eggs, sugar, flour, baking powder, vanilla, and milk using a hand mixer. Slowly stir in the melted butter. Pour into your prepared dish.
03 -
Combine room-temperature butter, cinnamon, sugar, and a bit of flour until smooth and creamy.
04 -
Scoop chunks of cinnamon mixture onto the batter. Use a knife to swirl it all around to form a pattern.
05 -
Bake in the oven for 35 to 40 minutes. It's done when a knife inserted in the center comes out neat.
06 -
Stir together powdered sugar, milk, and vanilla until smooth. Drizzle it over the warm cake before serving.