In a large mixing bowl, combine the brownie mix, egg, water, and vegetable oil, whisking until smooth. Do not include the chocolate syrup packet at this time
Line a cookie sheet with parchment paper to prevent sticking and make cleanup a breeze
Evenly spread the brownie batter over the parchment paper using a rubber spatula
Bake at 325°F for 20-25 minutes. For fudgier brownies, remove them at the 20-minute mark; for a firmer texture, bake closer to 25 minutes. Let them cool completely to room temperature before cutting to get clean, even heart shapes
Remove from oven and let cool
Use a heart-shaped cookie cutter to cut the brownies into heart shapes
Snip a small corner off the chocolate syrup packet and drizzle the syrup over each heart-shaped brownie, either in a decorative pattern or generously covering them for an extra dose of chocolaty goodness
Sprinkle each brownie with red, white, and pink Valentine's Day-themed sprinkles