Place olive oil, lime juice, lime zest, tequila, taco seasoning, and brown sugar in a gallon-sized Ziplock bag and mix until well incorporated.
2 tablespoons olive oil, ¼ cup freshly squeezed lime juice, 4 teaspoons lime zest, ¼ cup tequila, 1 ounce taco seasoning, 3 tablespoons dark brown sugar
Add the salmon filets and gently rub the marinade over the salmon. Close the bag and marinate it in the fridge for at least 2 hours.
4 skin-on salmon filets
When ready to cook, preheat the oven to 425°F. Line a baking sheet with foil and spray it lightly with nonstick cooking spray.
Remove the salmon from the marinade and place it, skin-side down, on the baking sheet.
Place the baking sheet on the middle rack of the oven and roast it for 4-6 minutes per half-inch thickness of salmon. Measure the salmon at the thickest part. 4 minutes will give you salmon with a pink center (medium-rare) and 6 minutes will be thoroughly cooked through.
Remove the cooked salmon from the oven and transfer to plate. Remove the skin before placing the salmon on the mixed salad.