Preheat it to 300ºF(150ºC). If you don't want to make your bananas completely black, set your oven to the lowest setting instead. This will normally be about 170°F (77°C). Cover the baking sheet with parchment paper to catch leaks from the mushy bananas. Place unpeeled bananas on this sheet. Don't crowd them, as you want the warm air to circulate. Turn the oven light on so you can keep an eye on the bananas. Watch the bananas blacken, and check on them after the first 15 minutes to see if they've softened. If they don't seem soft after 30 minutes, you might want to try them for another ten. Once your bananas are out, you can poke them gently with a spoon to see if they're soft. Wait until they're cool enough to handle before adding them to your banana bread ingredients. If you're not ready to use them yet, you can store them in your fridge without losing any flavor. Cut off the tip of the peel with a pair of scissors, then squeeze the banana from the bottom to push out the fruit. Alternatively, you can just slice the peel down the side and topple the banana out, or scoop it with a spoon.

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Write a summary of the previous text in Vietnamese:
Bật lò nướng. Cho chuối chưa bóc vỏ lên khay nướng được lót giấy. Nướng chuối trong 20-30 phút. Lấy khay chuối ra và để nguội. Dùng chuối để chế biến món ăn.