Yucca mini tamales (Empanaditas de Yucca)

Ingredients

• 2 pounds frozen yucca
• 1/2 cup olive oil (plus more for brushing)
• 2 ounces annatto seeds
• 3/4 cup low-fat (1 percent) milk
• 1 pound lean ground beed
• 1 onion, chopped
• 2 cloves garlic, minced
• 1 green cubanella or Anaheim pepper (3-4 ounces)
• 1 tomato, chopped
• 1 teaspoon dried oregano
• 2 tablespoons fresh cilantro, chopped
• 1 piquillo pepper or pimientos, chopped
• 1 tablespoon capers, rinsed and drained
• 1/3 cup raisins
• 8-10 pimiento-stuffed green olives, chopped
• 2-3 large plantain leaves, cut into 24 (4x8inch) rectangles