Mash the avocado with the garlic, lemon juice and salt and pepper, to taste. Reserve covered in the refrigerator.
Preheat oven to 375 degrees F.
Cook the bacon in a medium saute pan until browned and crisp and transfer to a paper towel lined plate to drain. Crumble and reserve.
Pour off and reserve all the bacon fat. Saute the onion, garlic, and jalapeno seasoned with the cumin, coriander and salt and pepper, to taste, in a couple tablespoons bacon grease. On 2 tortillas sprinkle half of the grated cheese. Then layer equal amounts of the onion mixture, crumbled bacon, and the remaining grated cheese. Top with the other 2 tortillas.
Fry quesadillas in bacon grease turning until cheese is fully melted and the tortillas are crisp, about 5 minutes.
Cut into wedges and serve with the guacamole, sour cream and cilantro on top.