Peel one orange, slice it. Slice the other two oranges unpeeled.

Make the caramel. Simply melt the sugar in a pan on low heat, stir sometimes and add in the butter

Take a cake mold. Put the caramel first, the arrange the oranges, put the peeled one in middle

Make the tart though: mix the ingredients well. Make the dough into a flat circle shape and cover the oranges with it. Bake in the oven until fork comes out clean