Cook bacon in a large nonstick skillet over medium high heat, stirring often, until crisp (2-3 minutes). Reduce heat to medium and add onion and garlic. Stir until onion softens and caramelizes slightly, about 3-4 minutes. Add chard, pepper, and red pepper flakes. Stir until wilted, about 1-2 minutes. Don't overcook. Add chickpeas and roughly mash (I don't like to mash them completely( Stir to combine. Remove from heat.
Spread ¼ cup filling and cheese on half of each tortilla. Fold tortillas in half, pressing gently to flatten.
In a greased pan, add quesadillas and cook, turning once, until golden on both sides. Continue with the rest of the tortillas.