Preheat oven to 400 F. Lightly grease a baking sheet or line with parchment paper.
In a large mixing bowl, combine flour, cornmeal, salt, baking soda, baking powder, paprika and black pepper. Stir to combine. Add butter and cut into flour mixture with a pastry blender or two forks. Blend until mixture resembles coarse sand. Add diced prosciutto and cheese, stir to combine.
In a small bowl whisk together egg buttermilk and heavy cream. Pour into flour mixture, stir until just combined.
Turn out onto a well floured surface and pat into a large disk 3/4- to 1-inch thick. Cut into 8 triangles, or use a 2-1/2" biscuit cutter to cut into rounds and place on prepared baking sheet. Bake in preheated oven 12 to 15 minutes until light golden brown and firm to the touch. Let cool on baking sheet 3 to 5 minutes and transfer to cooling racks. Makes 8 scones.