What is the name of the sweet fruit spread often found in tarts and pies that is shown in the picture?

Fruit curd is a sweet dessert-y spread that's often found in tarts and pies or as part of a fancy British tea service. Fruit curds are distinctly different from jams or jellies or even preserves, since curds are made by cooking down fruit juice with sugar rather than the whole fruit. The result is a creamy spread that can be piped into pastries or just served plain and spread onto toast or biscuits.

The basic ingredients are beaten egg yolks, sugar, fruit juice, and zest, which are gently cooked together until thick and then allowed to cool, forming a soft, smooth, flavorful spread. Some recipes also include egg whites or butter.

Curds differ from pie fillings or custards in that they contain a higher proportion of juice and zest, which gives them a bolder, fruitier taste. Also, curds containing butter have a smoother and creamier texture than both pie fillings and custards, which contain little or no butter and use cornstarch or flour for thickening. Additionally, unlike custards, curds are not usually eaten on their own

Lemon is the primary flavor for fruit curd, but you could easily use grapefruit, orange, or lime too. Passion fruit, mango, rhubarb, raspberry, and blueberry is also great. All you really need is fruit juice.