Crab and Lentil Stuffed Tomato with Yogurt

Name: Crab-and-Lentil-Stuffed Tomato with Yogurt
Ingredients: 2 6-ounce cans crab meat; 1 cup canned lentils; 2 sliced celery stalks; 2 sliced green onions; 4 tablespoons pine nuts; 2 tablespoons chopped basil or oregano; Juice of half a lemon; salt; pepper; 1/2 cup Greek yogurt; 1 teaspoon curry powder; 6 large tomatoes