Ingredients

• 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

Instructions

1. Combine all ingredients in small bowl.
2. Do ahead: Can be made 2 days ahead. Store airtight at room temperature.
3. 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.
4. Do ahead: Can be made 3 hours ahead. Cover; chill.
5. Let beef stand at room temperature 1 hour.
6. 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.
7. *Available at specialty foods stores and from tienda.com.