Easy Blueberry Crisp

Bahan-bahan (6 porsi)

• 5 cups blueberries (fresh or frozen)
• 2 tablespoons granulated sugar
• 3 tablespoons all-purpose flour
• 1 lemon
• ¼ cup butter (softened)
• ½ cup brown sugar
• ¼ cup all-purpose flour
• ¾ cup oats (regular or quick)
• ½ cup sliced almonds (optional)
• ¼ teaspoon cinnamon