Thoroughly combine softened butter with jalapeño, lime juice, tequila (optional), salt, and pepper. Roll with plastic wrap into a log shape, 1 inch in diameter. Refrigerate 2 hours or until compound butter is solid. Make one day ahead, if possible.
Preheat Bravo and set to broil at 500°F.
Remove skirt steak from refrigerator and bring up to room temperature, 20 mins. Pat dry and season with salt and pepper.
Spray baking pan with cooking spray. Place steak on pan. Cook 4 min. Flip, and cook for an additional 3-4 minutes for medium-rare.
When done, remove. Let rest 5 minutes. Place slab of chili-lime tequila butter on meat and let melt to infuse flavor. Serve immediately.