2 tablespoons dark brown sugar
1 tablespoon sweet smoked paprika
1 tablespoon coarse kosher salt
1 1/2 teaspoons chipotle chile powder or ancho chile powder
1 teaspoon ground black pepper
3/4 cup olive oil
3 tablespoons Sherry wine vinegar or red wine vinegar
3 tablespoons fresh lemon juice
3 garlic cloves, peeled
2 medium shallots, peeled, quartered
1 teaspoon fine sea salt
1/2 teaspoon freshly ground black pepper
1/2 teaspoon dried crushed red pepper
3 cups (packed) stemmed fresh parsley
2 cups (packed) stemmed fresh cilantro
1 cup (packed) stemmed fresh mint
1 3 1/2-pound beef tenderloin
2 tablespoons olive oil
Combine all ingredients in small bowl. DO AHEAD Can be made 2 days ahead. Store airtight at room temperature.
Combine first 8 ingredients in blender; blend until almost smooth. Add 1/4 of parsley, 1/4 of cilantro, and 1/4 of mint; blend until incorporated. Add remaining herbs in 3 more additions, pureeing until almost smooth after each addition. DO AHEAD Can be made 3 hours ahead. Cover; chill.
Let beef stand at room temperature 1 hour.
Prepare barbecue (high heat). Pat beef dry with paper towels; brush with oil. Sprinkle all over with spice rub, using all of mixture (coating will be thick). Place beef on grill; sear 2 minutes on each side. Reduce heat to medium-high. Grill uncovered until instant-read thermometer inserted into thickest part of beef registers 130°F for medium-rare, moving beef to cooler part of grill as needed to prevent burning, and turning occasionally, about 40 minutes. Transfer to platter; cover loosely with foil and let rest 15 minutes. Thinly slice beef crosswise. Serve with chimichurri sauce