Cook the base: Prepare your rice or preferred grain according to package directions.
Fluff and keep warm. If using cauliflower rice, sauté it with a little olive oil and salt for 3–4 minutes until tender.
Season the shrimp: Pat the shrimp dry with paper towels. In a bowl, toss with olive oil, chili powder, cumin, smoked paprika, garlic powder, onion powder, salt, and pepper until evenly coated.
Cook the shrimp: Heat a large skillet over medium-high.
Add the shrimp in a single layer. Cook 1.5–2 minutes per side, just until pink and opaque. Remove from heat and squeeze half a lime over the top.
Warm the beans and corn: In the same skillet (no need to wash), add the black beans and corn with a pinch of salt.
Cook 2–3 minutes until warmed through. If you like, add a splash of lime juice and a dash of chili powder.
Prep the fresh toppings: Halve the tomatoes, slice the onion, shred the cabbage, chop the cilantro, and dice the avocado. Set out lime wedges.
Assemble the bowls: Divide the rice among bowls.
Top with beans and corn, then the shrimp. Add tomatoes, cabbage, onion, avocado, and cilantro. Finish with lime juice and any optional toppings like salsa, Greek yogurt, or a sprinkle of cotija.
Adjust and serve: Taste and add more lime, salt, or hot sauce as needed.
Serve immediately while the shrimp are still warm.