Preheat the oven to 425 degrees . In a medium bowl, combine the cheese, canned chiles, sour cream (or crema), yellow onion, garlic, chopped cilantro and cumin.
Heat 1/4 inch oil in a skillet over medium heat until hot. Using tongs, add 1 tortilla at a time, turning in the oil to soften for a few seconds. Drain on paper towels.
Dollop a few tbsp. of the cheese mixture onto each tortilla and roll up like a cigar (you will use about half to two-thirds of your filling). Arrange the enchiladas in a single layer in a casserole dish. Cover with the remaining cheese mixture and bake until golden, about 15 minutes. Top with the jalapenos, red onions and whole cilantro leaves.