- 2 tablespoons butter
- 2 tablespoons all-purpose flour
- 1 1/2 cups milk
- 1 (5 ounce) can chunk light tuna in water, drained and flaked
- salt and ground black pepper to taste
- 4 slices bread, toasted, or to taste
- Melt butter in a small saucepan over medium heat. Stir flour into melted butter until smooth and slowly stream milk into the mixture while whisking continually. Bring mixture to a simmer and cook until thickened, about 5 minutes.
- Reduce heat to medium-low. Stir tuna into the milk mixture; season with salt and pepper. Cook until tuna is warmed, 2 to 3 minutes.
- Ladle tuna mixture over toasted bread to serve.