Sheet Pan Cauliflower Nachos

Name: Sheet Pan Cauliflower Nachos
Ingredients: 1 medium head cauliflower (about 1 1/2 pounds); 1 large bell pepper , any color; 1/2 large yellow or red onion; 2 tablespoons olive oil; 1 tablespoon taco seasoning (see recipe note); 1/2 teaspoon kosher salt , or to taste; 1/2 (15-ounce) can black or pinto beans , drained and rinsed ( 3/4 cup ); 1 to 1 1/2 cups shredded Monterey Jack or cheddar cheese; 1 1/2 cups shredded lettuce or thinly sliced cabbage; 1/2 lime; 1 large avocado, diced, or 1/2 cup guacamole; 1/3 cup salsa or pico de gallo