I have tried many times to make cream cheese frosting – but it's a tough one. Beating the cream cheese too long or too early in the frosting-making process adds too much liquid to the frosting, meaning it never really achieves the right consistency to be frosting.
After experimentation and research, here is the version that maintained its texture and did not become disgustingly runny.
Cream cheese frosting (a must for good carrot cakes or red velvet cakes):
1/2 cup unsalted butter
2 teaspoons vanilla
1/2 teaspoon salt
3 1/2 cups powdered sugar
226 grams of cream cheese
Start by beating butter, vanilla and salt until smooth. Add the powdered sugar until mixture is smooth. The mixture will be very stiff.
All at one time, mix in the cream cheese and mix on the slowest mixer setting for one minute. Scrape the sides of the bowl and beat again for another half-minute.
The frosting will still be somewhat stiff, but this is FAR superior to a dripping, watery mess that can be had otherwise.