Line a 9×13-inch baking pan with aluminum foil, letting some hang over the edges to make a sling. Lightly grease the foil with butter or nonstick spray. This makes it easy to lift the bars out later and keeps cleanup simple.
Preheat your oven to 350°F (175°C) while you mix the batter so it’s good and hot when the pan goes in.
In a large mixing bowl, add the dry chocolate cake mix and the eggs. Stir with a sturdy spoon until the eggs are mostly worked in. The mixture will be thick and a bit crumbly at this point.
Spoon in the entire can of cherry pie filling (cherries and all the syrup). Gently fold and stir until everything is well combined and no dry pockets of cake mix remain. The batter will be thick, glossy, and studded with cherries.
Pour the batter into the prepared, foil-lined pan. Use a spatula to spread it out evenly into the corners and smooth the top as best you can.
Sprinkle the chocolate chips evenly over the top of the batter, pressing them in very lightly with your hand or the back of the spatula so they stick but still show on the surface.
Bake on the center rack of the preheated oven for 25–30 minutes, or until the edges are set and pulling slightly away from the foil and the center looks just set. A toothpick inserted into the center will come out with moist crumbs but not wet batter.
Set the pan on a wire rack or cool stovetop and let the bars cool completely in the pan. They will firm up as they cool and be easier to cut.
Once cool, use the foil edges to lift the whole slab of bars out of the pan onto a cutting board. Cut into 12 squares (or smaller pieces if you like). Serve right away or store, covered, at room temperature for up to 3 days.
Variations & Tips
