(tart adapted from Maida Heatter’s Cakes/ganache from Dorie Greenspan’s Baking: From My Home to Yours)

FILLING (may be made a day or more ahead):

• 12 oz. walnuts
• 1-1/2 c. granulated sugar
• 1/2 c. water
• 7 oz. (14 TB) unsalted butter, at room temperature, cut into pieces
• 1 c. less 2 TB whole milk
• 1/3 c. honey

With a sharp knife, chop the nuts fine, into about 1/8″ slices or squares. If the pieces are too large, it will be difficult to cut the tart.

In a 3-quart saucepan, stir the sugar and water over moderate heat until sugar is dissolved and the mixture comes to a boil. Then boil without stirring until the mixture starts to turn color. Continue boiling, swirling the pan occasionally, until the mixture turns to a “rich butterscotch color.”

Remove pan from the heat. With a wooden spoon, slowly stir in the butter. When butter is incorporated, slowly stir in the milk. Simmer the mixture for 15 minutes, stirring occasionally. (If the mixture starts to curdle or sugary clumps form, whisk briskly and they should smooth out as the mixture cooks.) When the 15 minutes are up, stir in the honey and then the nuts.

Pour the mixture into a large bowl. Stir occasionally until it reaches room temperature, then cover and refrigerate. (If making filling ahead of time, bring back to room temperature, stirring occasionally, while you make the pastry.)

PASTRY:

• 3 egg yolks
• 1/3 c. cold water + more if needed
• 4 c. sifted all-purpose flour (sifted first, then measured)
• 1/4 c. granulated sugar
• 1/4 tsp. salt
• 9 oz. (18 TB) unsalted butter, cold, cut into 1/4″ to 1/2″ squares

Preheat oven to 475° F (that’s not a typo, it’s a hot oven), with a rack one-third up from the bottom.

Mix egg yolks and 1/3 c. water together with a fork.

Place flour, sugar, salt and butter in the bowl of large food processor.* Repeatedly pulse until butter is mostly though not completely incorporated. Then, slowly add the egg yolk/water mixture, pulsing. If too dry, add a little more water. As with any other pie crust, stop mixing before the mixture forms a ball.

*NOTE: If you don’t have a large processor, do it in two batches, put the processed mixtures in a large bowl and mix the liquid in by hand. Or use a stand mixer.

Turn the dough out onto a large piece of waxed paper. Squeeze together with your hands and knead just until the dough holds together. Form into a fat sausage-shaped roll. Chop off 1/3 of the dough and form it into a disk an inch or so high. (This will be the top of the tart.) Wrap loosely in waxed paper. Do the same thing with the remaining larger piece of dough. Let stand at room temperature for 20-30 minutes and no more.

Have ready a 9-1/2 or 10 x 1″ plain (not fluted) tart pan with straight sides.

On overlapping pieces of lightly floured waxed paper, roll out the larger dough piece into a 14″ circle. Place the tart pan in the middle and, using a sharp paring knife, cut the dough about 1-1/2″ larger than the circumference of the pan. Using the waxed paper, flip the dough into the pan, centering it. Pull off the paper and press the dough into place. You should have about 1/2″ of dough standing up above the sides all around.

Roll out the remaining dough on more waxed paper. Set the tart pan in the middle and cut the dough just a tiny bit larger than the circumference of the pan.

Spoon the cooled filling into the dough in the pan. The filling will be very sticky. Press it down firmly with your hands so that it is flat and completely fills the tart.

With lightly-floured fingers, thin out the raised rim of dough that extends around the filling. This is an important step because there will be double dough there and, if not thinned, it will not bake properly. Then, fold down the thinned rim over the filling, making sure that it is not pleated.

Lightly brush the folded-down dough with water. Then, place the smaller dough circle on top. Cut off any excess pastry and press the dough down with your fingers. Using the back of a fork (floured if necessary), press firmly down all around the outside to seal tightly. Then, using a sharp paring knife, make 2 or 3 vent slits near the center.

Bake the tart for 20-25 minutes. Watch it carefully. If the top starts to bubble up, flatten it with a metal spatula and/or make a small knife slit to release trapped air. If the top starts to get too brown, tent with aluminum foil.

Cool tart in the pan on a rack. Keep the oven on in case you need it again. Once cooled, cover the tart with a serving plate and flip it over. If (as happened to us) part of the bottom of the tart (the top once flipped over) has failed to properly brown, just put the tart back in the pan, cover with foil and bake a little longer. The tart is very sturdy and this won’t be a problem. Go through the cooling process again.

GANACHE:

• 8 oz. bittersweet chocolate, finely chopped
• 1 c. + 2 TB heavy cream
• 2 oz. (4 TB) unsalted butter, at room temperature, cut into 4 pieces
• 16 walnut halves

Put the chopped chocolate in a medium heatproof bowl.

Bring the cream to a boil. Pour half of it over the chocolate. Wait for 30 seconds and then, using a whisk or a spatula, gently stir the chocolate and cream together using a circular motion. Pour in the rest of the cream and repeat. When the ganache is smooth and shiny, add the butter pieces one at a time, gently mixing until each piece is blended before adding the next.

Leave ganache at room temperature, stirring occasionally until it thickens. You can hasten the process by refrigerating it, but watch it very carefully and stir often.

While ganache is cooling, lightly toast 16 walnut halves and let them completely cool.

Ice the top and sides of the cooled tart with the ganache, using an icing spatula. Place the walnut halves in a ring around the top. Refrigerate the tart. Cut the tart while cold, but bring slices to room temperature before serving