Preheat oven to 425 degrees. Into a large bowl sift together flour, baking powder, and salt. Cut butter into bits and with your fingertips or a pastry blender blend butter into flour mixture until mixture resembles coarse meal. Add milk and heavy cream, stirring with a wooden spoon until just combined (mixture will be wet).
Transfer dough to a well-floured surface and with floured hands turn dough to coat evenly. Knead dough gently 4 to 6 times, or just until smooth (do not overwork dough). Pat or roll out dough into an 8-inch round (slightly more than 1/2-inch thick).
Using a floured 2 to 2 1/2-inch star-shaped or round cutter cut out biscuits and arrange about 1-inch apart on baking sheets. Gently pat out or roll out dough scraps and cut out more biscuits in same manner.
Bake biscuits, 1 sheet at a time, in middle of oven until pale golden and cooked through, 10 to 12 minutes. Transfer biscuits as baked to a basket lined with a cloth and cover with cloth to keep warm and moist.
Serve biscuits with butter.