Cut butter into thirds and bring it to room temperature.
In a small saucepan, combine egg yolks, water, lemon juice, salt and pepper. Add a piece of the butter. Cook over medium-high heat, stirring rapidly with a whisk, until butter melts and sauce begins to thicken.
Add the remaining butter, one piece at a time, stirring constantly until melted. Continue to cook and stir until sauce thickens. Remove from heat.
Stir in dried dill and capers. *If sauce is too thick or curdles, immediately whisk in 1-2 Tbsp. hot water.
Spoon desired amount over strata.
(Recipe adapted from Better Homes & Gardens New Cook Book)