Tian mian jiang is a thick, dark brown- or black-colored Chinese sauce made from wheat flour, sugar, salt, mantou, and fermented yellow soybeans (the lees left over from the fermentation of soybeans to make soy sauce). Translation of the term into English includes sweet bean sauce, sweet bean paste, sweet soybean paste, sweet flour sauce, or sweet noodle sauce.

There are many different types of sweet bean sauces depending on the different compositions and the different method of production, and each variation represents the unique local style of a particular region, and even within the same geographical region, different manufacturers produce different kinds of sweet bean sauce. For example, in northern China, the use of sugar is far less than in southern China in terms of the amount added, while the usage of mantou flour as the main ingredient is a much more common practice. Traditionally, in these regions, a good brand of sweet bean sauce is considered top quality when its sweet taste results not from the addition of sugar, but as a direct result of the fermentation of the starches contained in the sauce's ingredients.

Bean ( /ˈbiːn/) is a common name for large plant seeds of several genera of the family Fabaceae (alternately Leguminosae) some of which are used for human food or animal feed.

The term "bean" originally referred to the seed of the broad bean, but was later expanded to include members of the genus Phaseolus, such as the common bean and the runner bean, and the related genus Vigna. The term is now applied generally to many other related plants such as soybeans, peas, chickpeas (garbanzos), vetches, and lupins.^{[citation needed]}

"Bean" can be used as a synonym of "pulse," an edible legume, though the term "pulses" is usually reserved for leguminous crops harvested for their dry grain, and usually excludes crops used mainly for oil extraction (such as soybeans and peanuts) or those used exclusively for sowing purposes (such as clover and alfalfa). Leguminous crops harvested green for food, such as snap peas, snow peas, and so on, are classified as vegetable crops.^{[citation needed]}

In English usage, the word "bean" is also sometimes used to refer to the seeds or pods of plants that are not in the family leguminosae, but which bear a superficial resemblance to true beans—for example coffee beans, castor beans and cocoa beans (which resemble bean seeds), and vanilla beans which superficially resemble bean pods.

In cooking, a sauce is liquid, creaming or semi-solid food served on or used in preparing other foods. Sauces are not normally consumed by themselves; they add flavor, moisture, and visual appeal to another dish. Sauce is a French word taken from the Latin salsus, meaning salted. Possibly the oldest sauce recorded is garum, the fish sauce used by the Ancient Romans.

Sauces need a liquid component, but some sauces (for example, pico de gallo salsa or chutney) may contain more solid elements than liquid. Sauces are an essential element in cuisines all over the world.

Sauces may be used for savory dishes or for desserts. They can be prepared and served cold, like mayonnaise, prepared cold but served lukewarm like pesto, or can be cooked like bechamel and served warm or again cooked and served cold like apple sauce. Some sauces are industrial inventions like Worcestershire sauce, HP sauce, or nowadays mostly bought ready-made like soy sauce or ketchup, other are still freshly prepared by the cook. Sauces for salads are called salad dressing. Sauces made by deglazing a pan are called pan sauces.