Red Velvet Chocolate-Swirled Brownie Bars

"These easy, no-mixer brownie bars are in between a bar and a brownie. Not supremely fudgy to give them true brownie status, but much fudgier and richer than your typical bar, and not cakey. They're smooth, rich, dense, and supremely moist. I bought two sets of Betty Crocker gel food coloring (with red, blue, yellow, and green) in order to get two reds vials. Use whatever kind of food coloring you like; you'll need lots of it in order to dye the chocolaty batter red. They're squishy soft in the interior, with slightly firmer and chewier edges. The chocolate swirls add a nice burst of chocolate, without being overly chocolaty in order to stay true to red velvet. They're buttery, velvety soft, and perfect for Valentine's Day or Christmas!..."