Adapted from The Bread Bible, by Rose Levy Beranbaum.
Cut the butter into 3/4 inch cubes and refrigerate for at least 30 minutes. Whip the cream until soft peaks form when the beater is lifted; cover and place in the refrigerator.
Place a baking stone or large baking sheet on a rack in the middle of the oven. Preheat the oven to 400 F. Line a second, smaller baking sheet with parchment paper.
In a large bowl, whisk together the flour, sugar, baking powder, salt, and lemon zest. Add the chilled butter cubes and cut the butter in with a pastry blender, or rub in with your fingers, until the mixture resembles fine meal. Make a well in the center and add the whipped cream.
Using a rubber spatula or wooden spoon, fold in the whipped cream. Then knead the dough in the bowl until it just comes together.
Turn the dough onto a very lightly floured surface and knead about eight times, until it can be shaped into a smooth ball.
Cut the dough in half, and press each half into a rectangle of approximately 5 inches by 7 inches. Wrap each rectangle in plastic wrap and freeze for 20 minutes.
Using a 2-inch biscuit cutter, cut six rounds from each dough rectangle. Re-roll the scraps and place back in the freezer. Meanwhile, place the cut-out scones on the parchment lined baking sheet, and press an edible flower or a few petals into the top of each scone. Remove the remaining dough from the freezer, and cut out and decorate 3-4 more scones, placing them on the baking sheet. (If the baking sheet is full, you can place the remaining scones in the refrigerator and bake them later, after the first batch comes out of the oven.) Place the baking sheet in the freezer for five minutes.
Remove baking sheet from the freezer and brush the scones lightly with cream, being careful not to disturb the flowers.
Bake for 15-20 minutes, until the scones are just starting to brown. Remove from the baking sheet, and allow to cool on a wire rack.