Combine avocado, Mexican crema, cilantro, lime juice and lime zest in the bowl of a food processor; season with salt and pepper, to taste. With the motor running, add 1/4 cup water in a slow stream until emulsified; set aside in the refrigerator until ready to serve.
for the tacos
Heat canola oil in a large cast iron skillet over medium high heat. Add cauliflower and onion; season with salt and pepper, to taste. Cook, stirring occasionally, until browned, about 10-12 minutes.
Stir in garlic, chili pepper, cumin, oregano and cinnamon until fragrant, about 1 minute.
Stir in black beans and salsa. Reduce heat to low. Cook, stirring occasionally, until slightly reduced and flavors have blended, about 4-5 minutes; season with salt and pepper, to taste.
Serve immediately in tortillas, topped with avocado crema.
Notes
*Mexican crema is a creamy, slightly tangy condiment (similar to sour cream and crème fraîche) and is used in a range of Mexican dishes from soups to stews and as a topping for tacos, enchiladas, burritos, and more.