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How to Make Grilled Cheese Sandwich

You will need:

• 4 slices white bread
• 3 tablespoons butter, divided
• 2 slices cheese

How to make:

1. Preheat the skillet over medium heat.
2. Generously butter one side of a slice of bread.
3. Place bread butter-side-down onto skillet bottom and add 1 slice of cheese.
4. Butter a second slice of bread on one side and place butter-side-up on top of the sandwich.
5. Grill until lightly browned and flip over; continue grilling until the cheese is melted.
6. Repeat with remaining 2 slices of bread, butter and slice of cheese.

(Adopted from: https://www.allrecipes.com/recipe/23891/grilled-cheese-sandwich/ (April 21, 2019))

The main ingredient of the food is ____.