Line the bottom of a square pan with parchment paper or grease the bottom with butter.

In a microwave container, add the brown sugar, the white sugar, and the cream.

Cook in the microwave for 6 minutes.

Stir gently and cook for another 6 minutes.

Add the butter and beat with an electric mixer at high speed for about 2 minutes until the mixture becomes thicker.

Spread evenly in the pan and place in the refrigerator for 30 minutes.

Remove from the pan and cut into 1-inch squares.