Preparation Position 1 rack in top third and 1 rack in bottom third of oven and preheat to 450°F. Combine 41/2 cups flour, baking powder, and salt in large bowl; whisk to blend. Add butter cubes and rub in with fingertips until mixture resembles coarse meal. Add cream and half and half and stir just until mixture is moistened and begins to clump together. Turn out dough on floured work surface. Knead gently just until dough holds together, adding more flour by tablespoonfuls if dough is very sticky, about 6 turns. Roll out dough to 1/2-inch thickness. Using tines of fork dipped into flour, pierce dough all the way through at 1/2-inch intervals. Using 23/4- to 3-inch-diameter biscuit cutter or cookie cutter dipped in flour, cut out dough rounds. Transfer dough rounds to 2 ungreased rimmed baking sheets, spacing 1 inch apart. Bake biscuits until light golden brown and tester inserted into centers comes out clean, rotating baking sheets halfway through baking, about 14 minutes Total. Transfer biscuits to cooling racks and cool slightly. DO AHEAD: Biscuits can be baked 4 hours ahead. Let stand uncovered at room temperature. Place biscuits on ungreased rimmed baking sheets and rewarm in 375°F oven for 5 minutes before serving.
Preparation Position 1 rack in top third and 1 rack in bottom third of oven and preheat to 450°F. Combine 41/2 cups flour, baking powder, and salt in large bowl; whisk to blend. Add butter cubes and rub in with fingertips until mixture resembles coarse meal. Add cream and half and half and stir just until mixture is moistened and begins to clump together. Turn out dough on floured work surface. Knead gently just until dough holds together, adding more flour by tablespoonfuls if dough is very sticky, about 6 turns. Roll out dough to 1/2-inch thickness. Using tines of fork dipped into flour, pierce dough all the way through at 1/2-inch intervals. Using 23/4- to 3-inch-diameter biscuit cutter or cookie cutter dipped in flour, cut out dough rounds. Transfer dough rounds to 2 ungreased rimmed baking sheets, spacing 1 inch apart. Bake biscuits until light golden brown and tester inserted into centers comes out clean, rotating baking sheets halfway through baking, about 14 minutes Total. Transfer biscuits to cooling racks and cool slightly. DO AHEAD: Biscuits can be baked 4 hours ahead. Let stand uncovered at room temperature. Place biscuits on ungreased rimmed baking sheets and rewarm in 375°F oven for 5 minutes before serving.