If you love soft frosted sugar cookies but don't love rolling, cutting, and decorating dozens of individual cookies, these sugar cookie bars are the answer. They're buttery, extra soft, wonderfully chewy, and topped with a thick layer of creamy vanilla buttercream and colorful sprinkles. Best of all, there's no cookie dough chilling required, making them a quick and easy dessert for birthdays, holidays, and celebrations year-round.