For the tomatina picante: In a blender, combine the tomatoes, red pepper, chipotle chiles, garlic, cilantro, one teaspoon of the olive oil and cumin. Pulse until liquefied.
Heat the remaining olive oil in a medium sauté pan over high heat. Pour tomato mixture into pan. Bring to a simmer, then reduce heat to low. Keep on low heat, stirring occasionally, to let the flavors meld, 15 to 20 minutes. Remove from heat, keep warm. Season to taste with salt and/or pepper.
For the Tres Quesos Grilled Cheese: Layer Oaxacan cheese, queso fresco and manchego cheese on one slice bread. Top with other slice of bread.
Preheat a skillet or griddle. Spread the top and bottom of the outside of the sandwich with butter and place in the hot skillet. Press top of sandwich down with another skillet or heavier plate. Cook 1 to2 minutes, then flip sandwich to other side. Cook until heated through, cheese has melted and the bread is golden brown on the outside.
Slice sandwich in half and serve warm, with Tomatina Picante alongside.