Asparagus Tips in Puff Pastry and Lemon Butter Sauce

For the asparagus.

1. Trim the ends off the asparagus spears and peel from butt to near tip to remove the tough outer skin.
Choose a deep skillet or oval flameproof casserole large enough to hold the asparagus flat. Fill with water and bring to a rolling boil adding 1 1/2 teaspoons salt per quarter or litre of water.

2. Lay in the asparagus, cover until boiling point is reached, then uncover and boil slowly just until the asparagus is cooked through - 5 to 8 minutes or so depending on quality (eat a piece off the butt end to make sure). Remove immediately and arrange in one layer on a clean towel to cool.

3. Cut the tip ends of the spears into 5-inch (13-cm) and save the butt ends for a salad.

* The asparagus may be cooked in advance. When cold, wrap and refrigerate.

For the puff pastry rectangles.

Preheat the oven to 450° F / 230° C.

1. 15 minutes before serving, arrange the pastries (still frozen if you wish) on a baking sheet and brush the tops (not the sides) with the egg glaze. Brush a second coat, then make decorative knife cuts and crosshatchings on the surface.

2. Bake immediately in the middle level of the oven for 12 to 15 minutes until pastries have puffed up and browned and the sides have crisped.

* The puff pastry may be baked ahead of time and left in a switched off oven with the door ajar, (the sooner you serve them the more tenderly, flakily and buttery they will be.)

 Lemon butter sauce. (This is a beurre blanc sauce which takes only 3 to 4 minutes to make, but if you are not familiar with it, I suggest you do it just before serving since it is difficult to preserve.)

1. Boil the lemon juice, vermouth and ¼ teaspoon salt slowly in a small saucepan until liquid has reduced to about 1 tablespoon.

2. Then, start beating in the chilled pieces of butter, a piece or two at a time, adding another piece or two just as the previous pieces have almost melted - the objective here is to force its milk solids into a creamy suspension as the butter warms and softens, so that the sauce remains ivory coloured rather than looking like melted butter.

3. Season to taste with salt and pepper.

* The sauce can be kept on a small flame of a pilot light or anywhere that is warm enough to keep the butter from solidifying, but not so warm as to turn it into melted butter. However, if this happens you can beat over cold water until it begins to congeal and cream again.

Just before serving. 

• Finely chop the shallots or scallions

1. Melt 2 to 3 tablespoons butter in a frying pan, large enough to hold the tips in one layer.

2. Add the shallots or scallions and cook for a minute, then add the asparagus tips, shaking the pan by holding its handle to roll them over and coat with the butter. Season lightly with salt and pepper and roll once more.

To serve.

1. While they are still hot, split the pastries in half horizontally, arrange 3 or 4 hot and buttery asparagus spears on the bottom half, their tips peeking out of one of the ends, spoon a bit of the sauce over the asparagus, cover loosely with the top, and serve at once.

Remarks: Jacques Pepin, the famous French chef and teacher, based in Connecticut, has another version of the sauce where you add 2 tablespoons each of lemon juice and water to the rolling boil and rapidly beat in 1 stick (115 g) of soft butter in pieces. Bring the sauce to a rolling boil again for a few seconds, turn into a sauce boat and serve at once. This produces the same effect of a warm, creamy liaison of butter, rather than melted butter.