Whisk the flour, sugar, baking powder and salt in a large bowl. Cut the butter into the flour mixture using a pastry blender or your hands. Stir in the cream and yogurt. The dough will be shaggy, so use your hands to finish working the dough together.
Use a rolling pin to roll out the biscuit dough on a floured surface until about 1" thick. Use a 3-inch biscuit cutter or rim of a glass to cut dough into 8 circles. Reroll the dough as necessary. Place biscuits onto a cookie sheet lined with parchment paper. Brush the tops of the biscuits with more cream and sprinkle with coarse sugar.
Bake 13-15 minutes until slightly golden in color (the bottoms of the biscuits will be darker than the tops).