In a large pot, bring enough water to cover the asparagus to a boil. Add the trimmed asparagus and cook until tender, about 8 to 10 minutes. Drain the asparagus and set aside.

In the same pot, melt 3 tablespoons of butter over medium-low heat. Stir in the flour and cook for 2 to 3 minutes until the mixture is smooth and the flour has dissolved.

Gradually add the milk to the butter and flour mixture, stirring constantly. Add the cooked asparagus and salt. Continue to simmer the mixture, stirring frequently, until it has thickened, approximately 10 to 15 minutes.

Spread the remaining butter on the toasted slices of bread. Serve the creamed asparagus over the toast.