Top this cake with fresh or store-bought Meyer lemon cookies and these Candied Lemon Slices.
Preheat oven to 350 degrees. Sift together flour, cornstarch,and salt.
Beat butter, both sugars, juice, and zest in a mixeron medium speed until fluffy, about 3 minutes. Reducespeed to low. Add flour mixture in 3 batches, mixingwell after each. Divide dough into 4 pieces; wrap eachin plastic. Refrigerate 1 hour, or up to overnight.
Roll out each piece of dough on a sheet of flouredparchment until 1/8-inch thick. Place in freezer to set,about 15 minutes. Cut out cookies with a 2- or 2 1/4-inch fluted cutter, and place on a parchment-linedbaking sheet. (You can reroll scraps once beforedough begins to get tough.) Freeze another 15 minutes. Bake until edges just begin to turn goldenbrown, 14 to 15 minutes. Let cool on a wire rack.
Arrange 9 cookies in a circle on a 10-inch cake stand,edges touching. Place 2 cookies in center. Carefullyspread 3/4 cup honey mascarpone cream evenly overcookies, leaving a 3/4-inch cookie border. Repeat for 10more layers each of cookies and cream; then top witha final layer of cookies. Refrigerate cake and remainingcream at least 3 hours, or up to 12 hours. Just beforeserving, cover top layer of cookies with remaining.1 1/2 cups cream; decorate with candied lemon slices.