In a large skillet, heat olive oil over medium-high heat.
Add the sliced onion and cook until softened, about 3 minutes.
Add the garlic and cook for another 1 minute.
Add the chicken pieces to the skillet, stirring occasionally until browned, about 5-7 minutes.
Stir in the chopped chipotle peppers, adobo sauce, cumin, smoked paprika, chili powder, oregano, salt, and pepper. Cook for an additional 5-7 minutes, or until the chicken is cooked through and well coated with the sauce.
For the guacamole, cut the avocados in half, remove the pits, and scoop the flesh into a large blender.
Add lime, mayonnaise, salt, cumin, cayenne, and cilantro to the blender.
Pulse on high till all ingredients are well blended and guacamole is smooth. Transfer to a separate bowl.
Serve the tacos: heat tortillas on a dry cast iron skillet or in the microwave.
Fill each tortilla with a generous amount of the chipotle chicken mixture.
Top with purple cabbage, guacamole, Mexican crema or sour cream, feta, cilantro and lime.
Enjoy!