milk or ~2 ounces heavy cream

Milk is the lacteal secretion of mammals, predominantly derived from cattle (Bos taurus), though also produced by goats, sheep, and other species. Cow's milk is an emulsion of fat globules, proteins (primarily casein and whey), lactose, and minerals suspended in water, with a pale white to ivory color and creamy, slightly sweet flavor. The composition varies by breed, diet, and lactation stage; whole milk typically contains 3.5–5.5% fat, 3.2–3.4% protein, and 4.6–4.9% lactose. Milk exists in several standardized forms determined by fat content: whole milk (≥3.25% fat), reduced-fat or 2% milk, low-fat milk (1%), and skim milk (<0.5% fat).\n\nHeavy cream (also called heavy whipping cream) is the fat-rich portion of milk, separated during processing and containing a minimum of 36% milk fat in the United States (typically 36–40%), with lower fat percentages in other regions. It is thinner and more pourable than butter but richer than light cream, with a luxurious mouthfeel and mild dairy flavor that becomes more pronounced when whipped or heated.

Milk serves as a fundamental ingredient in both sweet and savory cooking, functioning as a liquid base for sauces (béchamel, mornay), custards, and puddings, while also enriching soups, braises, and baked goods. It is essential in beverages from hot chocolate to lassi, and as a cooking medium for grains and legumes. Heavy cream is valued for its ability to be whipped into stable peaks for dessert toppings and mousses, and as an enriching agent in sauces, soups, ice cream, and ganaches. In French cuisine, crème fraîche (cultured cream) and heavy cream anchor classic sauces; in Italian cooking, panna (cream) appears in pasta dishes like Alfredo; and in Indian cuisine, cream tempers spiced curries. Both milk and cream are indispensable in pastry and confectionery work, providing richness, structure, and emulsification properties.