A magnificent pastry stuffed with orange-scented cinnamon-sugar filling makes the perfect centerpiece to a festive brunch. Martha made this recipe on Martha Bakes episode 502.
Line a baking sheet with parchment paper; set aside. Cut Danish dough in half. On a lightly floured work surface, roll out each half to a 12-inch square. Transfer to prepared baking sheet, stacking the dough squares with a sheet of parchment paper between. Transfer to refrigerator; chill for 20 minutes.
Remove chilled dough from refrigerator. Transfer one dough square to lightly floured work surface. Place an 11-inch bowl, upside down, in the middle of dough and cut around bowl to form an 11-inch circle using a pastry wheel or sharp knife. Transfer circle of dough to a parchment-lined baking sheet.
Combine dark-brown sugar, cinnamon, zest, juice and salt in a small bowl. Spread mixture over dough circle, leaving a 1/2-inch border around perimeter. Repeat cutting process with remaining dough square. Brush border with beaten egg and cover with remaining piece of dough. Pinch edges to seal. Reserve egg wash.
Place a 3-inch bowl, upside-down, in the center of the 11-inch circle. Using a paring knife, cut dough circle into quarters from the center to the edge. Then cut each quarter into thirds.
Working with two adjacent portions of dough, twist away from one another in a full circle so that the top of the dough remains facing upwards. Repeat process working around the circle of dough. Pinch edges of twists together to seal. Cover lightly with plastic wrap. Let stand at room temperature until doubled in size, about 45 minutes. Brush with remaining egg wash.
Preheat oven to 375 degrees. Transfer to oven with a sheet of foil on the rack below. Bake until deep golden brown all over, 25 to 30 minutes. Let stand for 5 minutes on cookie sheet. Using a large spatula, slide Danish from parchment paper to a wire rack to cool completely.