Vegan Pizza - Health Nut Ninja

Ingredients

• 1 small head cauliflower, cut into small florets
• 1 tbsp. extra-virgin olive oil
• 1 tbsp. apple cider vinegar
• 1/2 tsp. garlic powder
• 1/2 tsp. cayenne pepper
• Kosher salt
• Freshly ground black pepper
• Cooking spray, for pan
• 2/3 c. barbecue sauce, divided
• 1 store-bought pizza dough
• 1/2 small red onion, thinly sliced
• 1/2 c. vegan mayonnaise
• Juice of 1/2 a lemon
• 1 tbsp. finely chopped chives, plus more for garnish
• 1 tbsp. finely chopped parsley
• 1 clove garlic, minced