In a small bowl, combine ground cumin, paprika, chili powder, onion powder, garlic powder, and chicken bouillon powder. Add salt and pepper to taste; I start with half a teaspoon of each. Set aside.
Heat olive oil in a large nonstick pan over medium-high heat. Add garlic and cook until fragrant, about 30 seconds. Stir in the spices and cook for 1 minute.
Add tomato paste and hot water to the pan, stirring until smooth. Simmer over medium heat for 2 to 4 minutes until slightly thickened.
Add the shredded rotisserie chicken to the sauce and toss until evenly coated. Adjust seasoning to taste with more salt, pepper, or a pinch of sugar if needed. Squeeze in fresh lime juice (I add 1 to 2 tablespoons). Remove from heat.
If desired, divide 1 cup of cheese among the bottoms of the taco shells and broil for 1 to 2 minutes until melted. Fill the shells with chicken and sprinkle the remaining 1 cup of cheese on top—it will melt from the warm chicken. Add your favorite toppings like lettuce, tomatoes, avocado, and sour cream. Serve immediately!
