Step 1 Preheat oven to 200°C. Place a large non-stick frying pan over medium–high heat and spray with olive oil. Add red onion and cook, stirring, for 4 minutes, or until soft.
Step 2 Add chilli powder to frying pan and cook, stirring, for 30 seconds, or until fragrant. Add beef mince and cook, breaking up mince with a wooden spoon, for 3–4 minutes, or until browned. Stir kidney beans through beef-mince mixture and remove pan from heat.
Step 3 Spread cauliflower crusts with an even layer of tomato paste. Top crusts with mince mixture, zucchini and capsicum, then scatter with mozzarella.
Step 4 Place pizzas in oven and cook for 10 minutes, or until cheese is bubbling and golden.
Step 5 Meanwhile, combine avocado, cherry tomatoes and coriander in a small bowl to make salsa.
Step 6 Cut pizzas into slices and serve with a side of avocado salsa.