In wide, shallow dish, cover skewers with water and let stand 30 minutes. Meanwhile, in blender or food processor with knife blade attached, purée garlic, 3/4 cup coconut milk, brown sugar, lime juice, fish sauce, ginger and tumeric.
Thread beef onto skewers; place in medium, deep bowl. Pour 1/2 cup coconut milk mixture over beef skewers and rotate to coat evenly. Refrigerate 30 minutes.
In small saucepot, heat onions, peanut butter, soy sauce, red pepper flakes, remaining 1/2 cup coconut milk and remaining coconut milk mixture over low heat until mixture simmers, stirring occasionally with whisk. Cook 2 minutes; remove saucepot from heat
Prepare outdoor grill for direct grilling over medium-high heat. Remove beef from marinade; discard marinade. Place skewers on hot grill rack and cook 4 to 5 minutes or until cooked through, turning once. Serve beef saté with peanut sauce for dipping