In a blender or food processor combine the garlic, chili powder, paprika, chipotle chilies, pineapple juice, vinegar and 1 cup of the pineapple chunks. Blend until completely smooth. Heat the olive oil in a large skillet over medium heat. When the oil shimmers, add the cauliflower, onions, and a pinch each of salt and pepper. Cook for 12-15 minutes or until the cauliflower is tender and the onions have caramelized. Reduce the heat to low stir in the pineapple sauce, the remaining cup of pineapple chunks and the jalapeño. Simmer for 8-10 minutes or until the sauce has reduced and coats the cauliflower, there will still be sauce left in the pan. Remove from the heat and stir in the cilantro.Meanwhile, stir together the avocado, lime juice and zest, and a pinch of salt. Lay the tortillas flat on a clean counter. On top of 2 tortillas, evenly layer the cheeses and cauliflower, then lay the remaining 2 tortillas on top. Heat the olive oil in a large skillet over medium heat. When the oil shimmers, place the quesadillas, one at a time, in the skillet and cook until golden on each side, about 4-5 minutes per side. Serve topped with avocado and grilled pineapple.