Prepare oven and preheat to 350F. Also, prepare a cake pan by lightly greasing it with butter.

Add butter and sugar in a bowl, and whisk until blended and fluffy using a hand mixer at medium-high speed.

Then reduce the speed of the hand mixer to medium and slowly add eggs one by one; keep mixing, and add lemon extract and vanilla extract. Then add sour cream and milk.

Add flour and cake mix at this stage, and beat well until fully incorporated. Transfer the batter to the prepared cake pan.

Place the pan in the preheated oven and bake for 50 to 55 minutes until inserted toothpick comes out clean.

Once ready, remove from oven, allow to cool for 10 minutes, then slice and serve.