CHOCOLATE PRALINE CROQUEMBOUCHE

Steps:

• Make cream puffs:
• Preheat oven to 425°F. and butter and flour 2 baking sheets.
• Spoon pâte à chou into a large pastry bag fitted with a 1/2-inch plain tip and pipe about 55 mounds onto baking sheets, each about 1 1/2 inches in diameter, leaving 1 1/2 inches between mounds. With a finger dipped in water gently smooth pointed tip of each mound to round puffs. Bake puffs in upper third of oven 10 minutes, switching position of sheets in oven halfway through baking if necessary. Reduce temperature to 400°F. and bake puffs 20 minutes more, or until puffed and golden. Let puffs stand in turned-off oven 30 minutes. Transfer puffs to racks to cool. With a skewer poke a 1/4-inch hole in bottom of each puff. Puffs may be made 2 days ahead and kept in an airtight container. Recrisp puffs in 400°F. oven 5 minutes and cool before filling.
• Make filling:
• In bowl of a standing electric mixer beat pastry cream until just smooth and soft enough to fold in heavy cream (do not overbeat). In a chilled bowl with cleaned beaters beat heavy cream until it holds soft peaks and fold in praline powder. Fold whipped cream mixture into pastry cream. Chill filling, covered, about 1 hour, or until cold.
• Fill cream puffs:
• Transfer filling to a large pastry bag fitted with a 1/4-inch plain top and barely fill each puff (do not overfill), putting filled puffs in a shallow baking pan.
• Make caramel:
• In a heavy saucepan stir together sugar and water and bring to a boil over moderately low heat, stirring and washing down sides of pan with a brush dipped in cold water to dissolve any sugar crystals until sugar is dissolved. Boil syrup over moderately high heat, without stirring, until it begins to turn pale caramel. Still without stirring, gently swirl syrup in pan (so that it colors evenly) until it begins to turn golden caramel and remove from heat. Caramel will continue to color slightly off heat and will thicken as it cools. As caramel begins to reach thickness of corn syrup, return pan to a burner at lowest possible heat, using a flame-tamer if necessary, and keep warm (do not simmer).
• Assemble croquembouche:
• Line a tray with wax paper. Working quickly with 1 cream puff at a time, impale bottom of each puff on tip of a small serrated knife and carefully dip top in caramel, leaving bottom 1/3 inch uncoated (to facilitate handling) and letting excess drip off. (Be extremely careful when working with hot caramel.) Set puff, coated side up, on prepared tray. When all puffs are coated, center 3, touching to form a triangle, on a cake-decorating turntable. Form a ring of 9 puffs around triangle and, working with 1 of the 9 puffs at a time, carefully dip 1 edge into caramel, letting excess drip off, and affix puffs to one another in a tight ring around first 3 puffs. Dip bottom of a puff in caramel and center it over middle of first 3 puffs. Working with 1 puff at a time, carefully dip 1 edge of each puff into caramel, letting excess drip off, and build a second, slightly smaller ring on top of the first using 8 puffs (if necessary adding an additional puff in center to stabilize ring), making sure each puff is glued with caramel to the one before it.
• Build on top of first 2 rows 4 more rings of 5 puffs each in same manner, always building from inside out with an additional puff in center as support.
• For top of croquembouche build 1 layer of 3 puffs and top with 1 puff. Let caramel harden 5 minutes and loosen croquembouche from turntable with a spatula. Transfer croquembouche with hands to a platter.
• Slip 5-inch-wide bands of wax paper under edges of croquembouche to protect from caramel drips. Remove caramel from heat and cool to thickness of molasses, 2 to 3 minutes. Dip tip of a small spoon in caramel and drizzle caramel decoratively over croquembouche. (Alternately, all puffs may be dipped in initial caramel and put in a shallow serving bowl without being molded into a cone shape.) Let caramel harden and remove wax paper. croquembouche is best served as soon as possible but may be made up to 12 hours ahead and chilled but not covered.
• To serve croquembouche, lightly shatter caramel cage with back of a knife and dismantle, 1 puff at a time.