Preheat the oven to 350 F and set aside a 9x13" casserole dish lightly greased with avocado oil.
Heat the avocado oil in a pan over medium heat. Add the diced onion and cook for 3-4 minutes until slightly translucent. Add the garlic and cook for another 1-2 minutes. Set aside and allow to cool slightly before combining with the shredded beef and 1/2 cup of enchilada sauce.
Add 1/2 cup of the enchilada sauce to the casserole dish and spread evenly.
If using the Siete almond flour tortillas, heat for 15 seconds to slightly soften. Add 3-4 spoonfuls of the shredded beef to the center of one tortilla and roll tightly. Add to the casserole dish. Repeat for all of the tortillas.
Top the tortillas with the remainder of the enchilada sauce and spread evenly.
Transfer to the oven and bake for 15 minutes or until fully warmed.
Allow to cool slightly before with topped with avocado, cilantro, green onion, lime wedges, and other toppings of your choice.