Stir in the cornstarch mixture and heat to a boil. Cook and stir until the mixture boils and thickens. Add the remaining butter and cook and stir until it's melted. Serve the sauce with the fish.
Always use warm, not hot, melted butter. If the sauce splits, whisk in a splash of cold water to re-emulsify ... Whether you’re topping a piece of baked salmon with a velvety Hollandaise or seasoning ...
The sauce is bursting with sharpness and samphire ... a large plate and season with salt and pepper. Spread the butter on top of each salmon fillet and press the fillets, buttered-side down ...
Hollandaise is a deceptively simple combination of melted butter and warm egg yolks whisked together, but it only comes together under specific conditions.
Meanwhile to make the sauce, strain the salmon poaching liquid through a sieve into a jug or bowl. Heat the butter in a small saucepan, once melted stir in the flour and beat to make a roux.