Sauce Mousseline — Hollandaise with Whipped Cream

Mousseline is hollandaise lightened with whipped cream — a sauce of extraordinary delicacy, airy where hollandaise is rich, gentle where hollandaise is assertive. It is the sauce for poached salmon, steamed asparagus, and any dish where the protein is mild enough to be overwhelmed by standard hollandaise's butter-forward intensity. Prepare a hollandaise by the standard method, but pull it slightly thinner than normal — the whipped cream will provide additional body. Season with salt, lemon juice, and white pepper. The hollandaise should be at approximately 55°C — warm enough to remain liquid but cool enough that it will not melt the whipped cream on contact. Whip 150ml of cold heavy cream (35% butterfat minimum) to soft peaks — not stiff peaks. Stiff cream folded into hollandaise creates a sauce with an unpleasant mousse-like texture; soft peaks integrate smoothly and maintain the sauce's pourable quality. Fold the cream into the hollandaise in two additions, using a large balloon whisk in broad, gentle strokes. The cream should disappear into the sauce, lightening its colour from deep gold to pale yellow and changing its texture from heavy to almost cloud-like. The finished Mousseline should be the palest yellow, barely holding its shape on a spoon, with a texture that dissolves on the tongue. It tastes of butter and cream in equal measure, with the lemon providing lift. If the hollandaise base is correct, the cream addition makes it forgiving: the additional fat from the cream actually stabilises the emulsion, making Mousseline slightly easier to hold at service temperature than plain hollandaise. The quality test: if you tilt a spoon of Mousseline, it should flow slowly in a thick ribbon, not hold its shape or run off the edge. Think of heavy cream that has been barely whipped — liquid but with body. In many modern kitchens, Mousseline has replaced hollandaise as the default warm butter sauce, particularly for fish. Its lighter body and lower butter intensity make it more versatile, though purists argue it lacks the definitive richness that is hollandaise's reason for existing.