Make the Orange Shortbread Base:
Preheat oven to 350°F (175°C). Line a 9x13-inch baking pan with parchment paper, leaving overhang on long sides for easy removal.

Pulse flour, powdered sugar, salt, and orange zest in a food processor until zest is distributed. Add cold butter and pulse until mixture resembles coarse sand with some pea-sized pieces.

Add egg yolk and orange juice. Pulse just until dough begins to clump—do not overprocess. Overworking creates toughness, which was part of the original critique.

Press dough evenly into prepared pan using the bottom of a measuring cup or your fingers. Prick all over with a fork.

Bake 18-20 minutes until pale golden and set. The base should be firm but not deeply browned—it will bake again with the sponge layer. Cool 10 minutes.

Prepare the Almond Sponge:
In a stand mixer with paddle attachment, cream butter and sugar until light and fluffy, 3-4 minutes.

Add eggs one at a time, beating well after each addition. Scrape down bowl between additions.

In a separate bowl, whisk together almond flour, all-purpose flour, baking powder, and salt.

Add flour mixture to butter mixture in two additions, mixing on low just until combined. Fold in orange zest, orange juice, and almond extract.

Spread batter evenly over par-baked shortbread base. Scatter flaked almonds over the top.

Bake 22-25 minutes until golden, springy to touch, and a toothpick inserted in center comes out clean. Cool completely in pan—this is essential before adding ganache.

Add the Turrón Layer:
Once sponge is completely cool, arrange thin slices of turrón blando in an even layer over the top. Press gently to adhere. If turrón seems dry, brush sponge lightly with honey before placing.

Make the Chocolate Ganache:
Place chopped chocolate in a large heat-safe bowl.

Heat cream in a small saucepan until just simmering—small bubbles around edges, steaming but not boiling.

Pour hot cream over chocolate. Let stand 2 minutes without stirring.

Starting from the center, whisk slowly in small circles, gradually working outward until completely smooth and glossy.

Whisk in butter until incorporated, then orange liqueur and salt.

Let ganache cool at room temperature, stirring occasionally, until it reaches a thick but pourable consistency—about 15-20 minutes. It should ribbon off a spoon and hold its shape briefly. Too-warm ganache will be 'sloppy' and run everywhere; properly cooled ganache sets beautifully.

Assemble:
Pour ganache over turrón layer, spreading gently with an offset spatula to cover completely and reach the edges. Work efficiently—ganache sets as it cools.

While ganache is still slightly tacky, scatter crumbled turrón, toasted flaked almonds, candied orange peel if using, and a few flakes of sea salt over the top in an attractive pattern.

Refrigerate at least 1 hour until ganache is fully set.

To Serve:
Using parchment overhang, lift traybake from pan. Use a sharp knife dipped in hot water (wiped clean between cuts) to slice into squares.

Serve at room temperature for best texture—the ganache softens slightly and the turrón becomes more yielding.