1 lb. (6 to 8 ) Tomatillos, husked and rinsed
1 medium white onion, sliced about ¼ in. thick
3 garlic cloves, peeled
Hot green chilies to taste (2 to 3 Serrano or 1 to 2 jalapenos), stemmed
1 ½ tbs. vegetable oil, plus extras for vegetables and tortillas
2 cups vegetable broth, plus a little extra if needed
½ cup Mexican Crema, crème fraiche or heavy whipping cream
8 cups cubed vegetables (about ½ in) such as carrots, onions, mushrooms and broccoli.
Salt
12 corn tortillas
2/3 cup shred Mexican cheese like asadero or Monterey Jack
Sliced onion white onion rings, for garnish
Fresh cilantro sprigs, for garnish
Roast Tomatillos, sliced onion, garlic and chilies on rimmed baking sheet 4 in below preheated broiler until Tomatillos are soft and blackened in spots on one side, 4 to 5 minutes. Turn vegetables over; broil about 4 minutes longer. Remove and reduce oven temperature to 400~F.
Scrap Tomatillo mixture into food processor or blender. Process until smooth puree. Heat 1 ½ tbs. oil in medium-large pot over medium-high heat. When drop of puree sizzles in oil add remainder of puree. Stir constantly for several minutes until darker and thicker. Add broth and crema, reduce heat to medium-low, partially cover, and simmer for about 30 minutes.
Spread cube vegetable on rimmed baking sheet. Drizzle with oil, sprinkle with salt, and mix to coat evenly. Place in oven and roast, turning vegetables regularly until crunchy-tender, about 25 minutes (reduce roasting time for broccoli and other green vegetables by 5 to 10 minutes).
If sauce has thickened and is no longer consistency of light cream soup, stir in more broth or water. Taste and season with salt, about 1 tsp. Lightly brush both sides of each tortilla with oil. Stack, wrap in damp paper towels, and microwave on high for 1 minute to warm and soften.
Smear about 1 cup of sauce over bottom of 13-by9in baking dish. Work quickly, roll equal portions roasted vegetables into each tortilla while tortillas are still hot and pliable. Place them side by side in baking dish. Douse evenly with remaining sauce. Sprinkle with cheese. Bake until enchiladas are heated through and cheese begin to brown, about 10 minutes. Garnish with onion rings and cilantro sprigs.

