1 small head broccoli (about 1/2 pound)
1 small head cauliflower (about 1/2 pound)
1 large carrot
1 large yellow onion
1 tablespoon olive oil
1/2 teaspoon salt
1 teaspoon chili powder, optional
1 cup rice, brown or white
1 15.5-ounce can black beans, drained and rinsed (about 1 1/2 cups)
2 cups shredded cheese (5 to 6 ounces)
2 cups crumbled tofu, shredded chicken, or shredded beef (meat should be cooked prior to assembling the burritos)
8 large burrito-sized flour tortillas (9- to 10-inches wide)
Optional extras: sliced avocado, sour cream, salsa, hot sauce, sliced scallions
Preheat the oven to 450°F. Line a baking sheet with parchment or a Silpat.
Chop the broccoli and cauliflower into bite-sized florets and stems. Chop the carrot into small pieces. Slice the onion through the root into wedges.
Toss all the vegetables together with the olive oil and salt, then spread in a single layer on the baking sheet. Roast until the vegetables are tender but still have some bite and have developed brown spots, 15 to 20 minutes. Stir the vegetables occasionally while they're roasting.
Remove the wedges of onion and roughly chop them into small pieces. Return the onion to the vegetables. Taste and toss with chili powder (if using) and additional salt if desired. Set aside.
While the vegetables are roasting, prepare the rice according to your package directions or by following our instructions for cooking brown rice or white rice. Once cooked, fluff and set aside.
To assemble the burritos, wrap one or more tortillas in a clean, damp dishcloth and microwave for about 20 seconds to soften. (This helps prevent the tortillas from cracking when you roll them.) Lay the tortilla on the counter and layer about 1/4 cup of cheese, about 1/4 cup rice, about 1/4 cup black beans, about 1/4 cup vegetables, and about 1/4 cup crumbled tofu on the lower third of the burrito. Any extras can go on top. Don't worry too much about the exact amount of each component. Aim for 1 to 1 1/2 cups total filling per burrito.
Roll the burrito tightly by folding the sides over the filling, then rolling from the bottom up. (See How to Wrap a Burrito.) If you're not eating the burrito immediately, wrap it tightly in foil and refrigerate for up to 12 hours; don't refrigerate burritos for more than 12 hours or they start to get soggy. Burritos can also be assembled, wrapped in foil,