Whisk all the ingredients for the Mexican BBQ Sauce in a medium bowl until well combined. Set aside.In a large skillet over medium-high heat, sauté the red onion for 3-4 min until softened. Add the garlic and sauté another minute.Add the red bell pepper and jalapeño and sauté 3-4 minutes, adding the additional 2 tbsp of water if necessary so the veggies don't stick to the pan.Pour the Mexican BBQ Sauce into the pan and simmer for about 10 minutes.Add the pinto beans, black beans, and corn and stir to combine. Simmer another 5 minutes to heat through.Taste and adjust seasonings as necessary or add salt/pepper to your liking.Add the chopped cilantro and stir.Serve hot on slider buns with guacamole and extra jalapeño slices.