1. Combine 1 tablespoon of the oil and 1 tablespoon of the vinegar and the lemon juice, whole garlic cloves, parsley, chives and horseradish or red pepper flakes in a food processor. Pulse to combine; season with salt and black pepper to taste. Set aside.
2. In a medium saucepan over medium-high heat, add 1 tablespoon of the olive oil and the minced garlic, shallots, celery, bell pepper and carrot; cook 3 to 4 minutes. Add the quinoa and cook 2 minutes, stirring constantly. Add the vegetable stock and bring to a boil. Reduce heat to low; cover and simmer 12 to 15 minutes or until water is absorbed. Mix in the chives and season with salt and black pepper to taste.
3. Heat a grill pan over medium heat. Drizzle the steaks with remaining olive oil. Season both sides with the cumin and salt and black pepper to taste. Cook steaks 5 minutes per side for medium rare. Remove from heat and let rest 10 minutes. Remove fat from edges and thinly slice steak against the grain.
4. Serve with quinoa and chimichurri.