In a square or rectangle shape microwave safe bowl add the butter and melt it in the microwave.
Add the ricotta cheese, milk powder and sugar and mix it well.
Microwave for 2 minutes, and give a mix.
After this we will not be mixing the ingredients. Microwave for 1 minute.
Again microwave for another minute… if the mixture is spilling hit cancel and wait for 10 -15 seconds before microwaving again.
Microwave again for 45 seconds to one minute. The total time it took was 5 minutes, in my microwave.
You will see that the milk cake is not jiggly and set and has brown color on the sides and in the bottom. Let cool for few minutes and cut to desired shape.