Three-Lettuce Salad

Ingredients

• 2 Tbsp. olive oil
• 2 Tbsp. red wine vinegar
• 1 to 2 cloves garlic, crushed
• 1/2 tsp. salt
• 3 Tbsp. brown sugar
• 1/2 bunch romaine lettuce, torn
• 1/2 bunch butter lettuce, torn
• 1/2 bunch leaf lettuce, torn
• 1 (11 oz.) can mandarin orange slices, drained
• 1 c. seedless red grapes, halved
• 1/3 c. chopped walnuts