The Tartine Confiture is the breakfast slice where the jam is the point and is allowed to be loud. One slice of bread, a thick layer of fruit preserve, eaten in the morning with coffee. It is the close cousin of the Tartine Beurre-Confiture, and the difference between them is one of emphasis: there the butter is the disciplined base and the jam a measured layer over it; here the fruit is the whole sweet idea and the butter, if any, recedes behind it. This is the tartine you make when what you want from breakfast is the jam.
The craft question is how a single slice carries a wet topping without giving up, and the answer is the preserve itself. A real confiture set with enough fruit and enough sugar holds together on the bread instead of weeping into it, so it sits as a glossy layer you bite through rather than a stain you taste. The fruit decides the character: a sharp blackcurrant or a tart apricot cuts against the wheat, a sweeter strawberry or fig leans into it, quince sets firm enough to hold an edge. The bread is usually baguette split lengthwise or a cut from a country round, and it wants enough crust to give the soft jam something to push against, because a slice that is soft on soft has no contrast left to offer. The slice is best soon after it is spread, before the crumb starts to draw the moisture down and the crust loses its bite.
The variations are the surrounding family, each a single change of topping for a single moment. Put butter under the jam with intent and it becomes the canonical petit-déjeuner, the Tartine Beurre-Confiture; take the jam away entirely and it is the plain Tartine Beurrée the morning is built on. Trade fruit for honey and you have the Tartine au Miel; trade it for chocolate and the slice moves to the afternoon goûter. The fruit varies with whatever was preserved, season by season and household by household. The Tartine Confiture belongs to the open-face tradition the catalog groups under Tartine, and its particular role is the breakfast slice that lets the jam, and not the butter, do the talking.