Cook the pasta according to the package directions. Drain and set aside.
Sprinkle 1 tablespoon fajita seasoning over the chicken and toss to coat.
Heat 1 tablespoon butter and 1 tablespoon olive oil in a heavy skillet over a high heat. When the butter has melted and the oil is hot, add half of the chicken in a single layer. Allow the chicken to brown, about 1 minute, before turning and cooking for an additional minute. Remove to a plate with a slotted spoon. Add the remaining chicken and repeat.
Add the remaining tablespoon each butter and olive oil to the same skillet. When the butter has melted, add the garlic, peppers, onions and mushrooms, then cook, getting as much color on the vegetables as possible, for 1 minute. Remove the vegetables to a plate.
With the skillet still over high heat, add the chicken stock and tequila to deglaze; allow to cook for a couple of minutes. Reduce the heat to medium, then sprinkle the remaining tablespoon fajita seasoning into the sauce. Stir in the cream and adobo sauce. Allow to cook, stirring, until the sauce begins to thicken, 2 to 3 minutes. Taste and adjust the seasoning as needed. (The sauce should have a good amount of heat to it.)
Finally, add the chicken and vegetables back to the skillet. Add the pasta and the tomatoes, then toss to combine. Cook for a couple more minutes until everything is heated through. Top with the chopped cilantro and chow down.