Take the puff paste, after it has received its last rolling, roll out evenly in a sheet one-fourth of an inch in thickness (you need not roll out the whole of the paste, but cut off a piece sufficient to make the number of tarts you wish, and roll them out). The sheet being ready, cut the number you require with a scalloped round cutter, about two and a half inches in diameter. Place them on the baking pans, having turned them over, bringing the bottom on the top. Next wash them with egg, or egg and water, then with a small, plain round cutter, one inch in diameter, make a mark in the center of each, pressing the cutter half through. Then just "dock" each in the center with the point of a knife or a fork (this is to prevent their blistering), now bake them. You will then find that the part marked with the small, round cutter has detached itself from the other part; this you remove with a penknife or a fork, and a hole will be left, into which pour what jam or jelly you intend using. This plan is far preferable for making the hole to receive the jelly than to place, as some recommend, sliced potatoes or small yieces of wood in the center, removing them when baked. These certainly form the hole, but their weight keeps down the pastry, and consequently it is not so light. By the plan I have given you obtain a good hole for the jelly without injuring the lightness of the pastry. Some add their jelly before baking, but that is wrong, as in baking the heat causes the jelly to boil, and it spreads itself over the tart and spoils its appearance.