Preheat the oven to 400 degrees. Don't bother removing the husks on the tomatillos--they'll help steam the tomatillos. Place the tomatillos on a baking sheet and roast for 15-20 minutes, or until they're tender with a fork. Allow them to sit until they're cool enough to handle. Remove the husks (use a fork as an aide if they're still hot) and add the tomatillos to the jar of a blender, along with the juice from the lime, jalapeño pepper, yellow onion, a pinch of salt and the cilantro. Pulse until completely combined. The mixture should be thick yet runny. If the salsa is too thick, add a squeeze or two of lime juice. Salt to taste. Set aside.
Start by washing your zucchini blossoms thoroughly. If your zucchini blossoms came with little zucchini stems, cut those off and slice them thinly. We're gonna use it all! Slice the teeny squash or zucchini in slivers.
To a small skillet, heat a tablespoon of olive oil over medium heat. When hot, add the zucchini stems and slivers. Cook for 2-3 minutes, until slightly softened. Add the ancho chile powder, salt and pepper; mix. Add the blossoms (flowers) and cook on both sides for 1-2 minutes. Remove from heat to cool slightly.
To assemble the quesadillas, add a handful or two (always go with more cheese) to a tortilla. Top with a few zucchini blossoms and sautéed zucchini. Place another tortillas right on top and transfer to a medium skillet. Cook on the first side for 2-3 minutes, covering the pan so the cheese gets super melty. Carefully flip and cook for an additional few minutes. Repeat with the second quesadilla and slice and serve with salsa.