A white sauce, often called a Béchamel, serves as a creamy, savory foundation for countless dishes, from baked pasta to rich casseroles and gravies. Traditionally, this texture is achieved by creating a roux, a cooked mixture of flour and fat. However, achieving a smooth, thick sauce without relying on flour is straightforward and opens up options for gluten-free or alternative dietary needs.
Using Starch Alternatives
Pure starches replace flour by thickening liquids through gelatinization. Cornstarch, arrowroot powder, and tapioca starch are highly effective, as their molecules absorb water and swell when heated. These starches must first be mixed with a cold liquid, such as water or milk, to form a smooth paste known as a slurry.
Adding dry starch directly to a hot liquid will cause the granules to clump instantly, resulting in a lumpy sauce. Use about one tablespoon of starch per cup of liquid for a medium consistency. Once the slurry is smooth, whisk it into the simmering sauce, where thickening occurs almost immediately.
Starch Properties
Each starch offers slightly different properties. Cornstarch is excellent for dairy-based sauces, while arrowroot powder is preferred for acidic liquids and provides a glossy finish. Tapioca starch is known for its high heat tolerance, making it suitable for sauces that require longer cooking times or baking. Arrowroot can lose its thickening power if overcooked, so it is best added toward the end of the process.
Creating Thickness with Dairy and Cheese
A rich white sauce can be created by manipulating the fat and water content of dairy, bypassing the need for a separate thickening agent. Using heavy cream or whole milk allows for reduction, where the liquid is simmered uncovered over low heat. As water evaporates, the remaining milk solids and fat become concentrated, naturally thickening the sauce and intensifying its flavor.
Incorporating soft, high-fat cheeses is an effective method, as the melted cheese acts as a powerful emulsifier and thickener. Cheeses like cream cheese, mascarpone, or soft goat cheese contain high levels of fat and protein that integrate smoothly into the liquid when melted. The proteins and fats form a stable matrix that traps water, creating a rich, velvety texture.
When adding cheese, the heat must be kept low to prevent the proteins from seizing and separating the fat, which results in a grainy or oily sauce. The cheese should be added in small portions, stirring constantly until fully melted and incorporated before adding the next batch. This gentle process ensures the sauce remains smooth and homogenous.
The Puree Method for Creaminess
For a method that adds nutritional value and body, whole, cooked solids can be blended directly into the sauce liquid. Mild-flavored vegetables like cauliflower, white beans, or potatoes are ideal because they contain starches and fiber that create a dense, creamy texture when pureed. The vegetable is first simmered until extremely tender, then transferred to a high-speed blender with the sauce liquid.
Blending the cooked solids until completely smooth creates a thick, velvety base that mimics the mouthfeel of a traditional cream sauce. This technique is useful for those seeking a lighter or vegetable-forward option. The resulting sauce can be thinned with additional liquid or thickened further by simmering it down after blending.
Nut and Seed Bases
Soaked nuts or seeds, such as cashews, can be blended with water to create a neutral-flavored “cream.” Soaking the cashews softens them, allowing a high-speed blender to break them down into a fine emulsion. This cashew cream can then be used as the foundation for a white sauce, providing a rich, dairy-free alternative with a smooth, decadent consistency.