Taco Salad with Mexican Polenta

I got this recipe for Mexican Polenta from Vegeterian Times and then tweaked it a little bit by making it into a salad.  They do provide a great recipe for a homemade Mexican seasoning, as follows:

Combine 1/2 tsp. chili powder, 1/4 tsp. cumin, 1/4 tsp. paprika, 1/4 tsp. cayenne pepper, and 1/4 tsp. salt.  

I highly recommend it! Much better than any store-bought version!

1 18-oz. tube polenta, cut into 12 ½-inch slices
2 Tbs. olive oil
1 large Vidalia onion, diced (1 ½ cups)
Juice of one lime
Mexican seasoning (prepared above)
3 cloves garlic, minced
1 tomato, diced
1 tsp. grated lime zest
1 15 oz. can low-sodium red beans rinsed and drained
1 15 oz. can low-sodium black beans rinsed and drained
½ cup shredded mozzarella cheese
3 Tbs. chopped cilantro
3 Tbs Tomatillo Salsa plus more for garnish ( I used Whole Foods brand)
3 Tbs Tequila Lime Red Pepper Salsa plus more for garnish ( I used Whole Foods brand )
4 cups fresh spinach
Blue Corn Tortilla chips ( I recommend Garden of Eatin Brand)

Position broiling pan 3 inches from heat, and turn broiler to high. Rub the polenta slices with extra virgin olive oil and place on a  baking sheet. Broil 6 minutes per side, or until browned.

Meanwhile, heat oil in large skillet over medium-high heat. Add onion, and cook 4 minutes, or until softened. Stir in lime juice, seasoning, garlic, and lime zest. Cook 4 minutes, or until onion is lightly browned. Add red beans, black beans, tomatoes, and both salsas; simmer 5 minutes, or until heated through. Add a tiny bit of water if it becomes too dry.

To serve, place a handful of tortilla chips on each plate/bowl. Top the tortilla chips with about a cup of fresh spinach. Top with the bean and tomato mixture. Arrange 3 pieces of polenta on top of  bean and tomato mixture. Sprinkle with mozzarella cheese and drizzle with more of both salsas, if desired.