Heat oven to 375°F. In large bowl, mix sugars, butter, vanilla and egg with spoon. Stir in flour and baking soda (dough will be stiff). In ungreased 12-inch pizza pan, spread or pat dough (or spread or pat dough in 12-inch circle on ungreased cookie sheet).
Bake 10 minutes. Sprinkle gumdrops over partially baked crust. Bake about 10 minutes longer or until edge of crust is golden brown. Cool in pan 30 minutes.
Place baking chips and shortening in small resealable plastic food-storage bag; seal bag. Microwave on High 1 minute. Squeeze bag until chips are melted and smooth. Cut off tiny corner of bag; drizzle melted chips over cookie. Let stand about 30 minutes or until set. To serve, cut into wedges.