1In a small bowl, combine 1/4 cup of the wine, 1/2 cup of the vinegar, half the minced garlic, half the minced shallots and 2 tablespoons of the oil. Pour into a large resealable plastic bag. Add steak, seal bag, and turn to coat. Refrigerate at least 8 hours, turning occasionally.
2Heat a large grill pan over medium-high heat. Remove steak from marinade, discard marinade. Pat steak dry with paper towels. Brush steak with 1 tbsp oil, and season with salt and pepper to taste. Place steak in grill pan. Cook 8 minutes per side. Reduce heat to medium-low; cook 4-5 minutes more or until an instant-read thermometer registers 125°F. Transfer to a cutting board and let stand 10 minutes.
3Meanwhile, for the sauce, in a small saucepan heat remaining 1 tbsp oil over medium-high heat. Add remaining minced shallots; sauté until soft. Add remaining garlic, cook 1 minute. Reduce heat to medium; add remaining 1/4 cup wine, remaining 1/2 cup vinegar, and raspberry preserves. Cook, stirring, 5 minutes or just until thickened. Season with salt and pepper to taste.
4Thinly slice steak across the grain. Place slices on a warmed serving platter, drizzle with sauce, and serve.