Baked Spring Rolls with Crab

Name: Baked Spring Rolls with Crab
Ingredients: 1 tablespoon vegetable oil or olive oil; 1/2 red bell pepper, chopped fine; 2 stalks celery from the heart, chopped fine; 6 water chestnuts, chopped fine; 1/2 small onion, chopped fine; 1/4 cup fresh bean sprouts, a handful, chopped; 2 (6-ounce) cans lump crab meat, drained, flaked; 2 tablespoons dark soy, such as Tamari; 1/2 teaspoon dried thyme leaves, eyeball it; 4 (13 by 17-inch) sheets defrosted phyllo dough; 3 tablespoons melted butter