Chocolate nut cake on a baking sheet

Ingredients:

Cake

• 4 cups premium flour + extra for work
• 1/3 cup granulated sugar
• 3/4 tsp salt
• 1/3 cup chilled shortening
• 220 g + 2 tbsp chilled unsalted butter, cut into small pieces
• 1 large egg yolk
• 0.5 - 3/4 cup ice water

Filling

• 4 cups salted roasted nut mix
• 2 cups semi-sweet chocolate chips (about 280 g)
• 110 g + 2 tbsp unsalted butter, melted
• 4 large eggs
• 1 and 1/4 cups light brown sugar
• 1 cup light corn syrup
• 1 tbsp. freshly squeezed lemon juice
• 1 tbsp vanilla extract
• Heavy cream to grease the dough

Preparation:

1. Cake:
   
   In a food processor, combine the flour, granulated sugar, and salt until evenly distributed. Add the shortening and pulse on high until the mixture resembles coarse meal. Add the butter and pulse a few times until it becomes the size of peas. Add the egg yolk and 1/2 cup of ice water and pulse a few times until the dough just begins to come together; if necessary, add up to 1/4 cup more water, 1 tablespoon at a time.
2. Place two sheets of plastic wrap on the countertop; place about three-quarters of the dough on one sheet and the remaining dough on the other. Gently flatten each piece of dough into a rectangle, using the plastic wrap as a guide. Wrap the dough tightly and refrigerate until firm, at least 2 hours and up to 24 hours.
3. On a lightly floured work surface, roll out the larger piece of dough into a 12 x 18-inch rectangle (about 0.75 inches thick). Transfer to a 11 x 15-inch baking pan, leaving a 1-inch overhang.
4. Filling:
   
   Grind the nuts in a food processor until coarsely chopped. Mix with the chocolate chips in a bowl, then evenly distribute the nuts and chocolate over the batter. In a bowl, combine the melted butter, eggs, brown sugar, corn syrup, lemon juice, and vanilla extract; pour over the nut mixture.
5. On a lightly floured work surface, roll out the smaller piece of dough into a 25x30cm rectangle; cut into 10 strips of dough, 2.5cm wide. Place 5 strips diagonally over the filling, about 2.5cm apart, then place the remaining strips perpendicular to the first.
6. Trim the strips along the edge of the baking sheet (you can use the scraps to lengthen any short strips). Fold in the overhanging edges, fold them under, and press them with your fingers. Brush the edges and the strips of dough with heavy cream. Refrigerate until firm, about 30 minutes.
7. Preheat oven to 375°F (190°C) and bake the pie until the crust is golden brown and the filling is set, 40-45 minutes. Transfer to a wire rack and let cool completely, at least 2 hours.