In the UK, what is known as "all-purpose flour" in the United States and Canada is typically referred to as "plain flour." Both all-purpose flour in the US/Canada and plain flour in the UK are similar in that they are versatile flours suitable for a wide range of baking and cooking applications.
Plain flour in the UK is a finely milled wheat flour that is neither self-raising nor strong (high-protein) flour. It contains an intermediate level of protein content, making it suitable for general baking purposes like cakes, cookies, muffins, pancakes, and sauces, where a moderate amount of gluten development is desirable.
It's essential to note that if you're looking for the equivalent of "self-raising flour" in the UK, you would need to add a leavening agent (usually baking powder) to plain flour. Self-raising flour in the UK already contains a raising agent, so it's not the same as all-purpose flour in the US or Canada, which is typically used interchangeably with self-raising flour for recipes that require leavening.
To summarize:
- "All-purpose flour" in the US/Canada = "Plain flour" in the UK.
- "Self-raising flour" in the UK is different from all-purpose flour and contains a leavening agent.