Preheat the oven to 425 degrees.
Line 2 baking sheets with parchment paper.
Heat the oil in a 12-inch skillet over medium heat.
While oil is heating, in a bowl smash 1 can of beans with the water with the back of a spoon or potato masher.
Once oil is shimmering, add in onions and cook until soft.
Stir in chili powder, cumin, oregano, lime zest, and 1/2 teaspoon salt. Add in the smashed beans and cook until thickened, for around 5 minutes.
Next add in corn and beans, then take off the heat. Add in cheese, lime juice, and cilantro.
Fill each half of a pepper with the filling and place on baking sheets.
Put both baking sheets in the oven, switch and rotate baking sheets halfway through baking time. Bake for 35-40 minutes. Season with salt and pepper to taste.