Cut beef cubes across grain in pieces 1/2" thick. Combine flour, salt and pepper; dredge meat with mixture. Brown meat in fat in Dutch oven or large pot. Add water, cover tightly and simmer 45 minutes. Stir in celery, carrots, onions, lentils, lemon juice, 1 1/2 tsp, salt and thyme. Simmer, covered, 1 hour stirring occasionally.
Makes about 8 servings