Preheat the oven to 350°F / 175°C. Line a baking sheet with parchment paper.

In a stand mixer fitted with the paddle attachment, mix together the flour, cocoa, baking soda, and salt on low speed, until just combined, about 15 seconds. Add the eggs, sugar, and vanilla, turn the speed up to medium, and mix until it just comes together into a thick but wet dough, for about 1 minute. Mix in the chocolate, nuts, dried cherries, and candied citrus until just combined.

You may need to stir with a rubber spatula to make sure they are evenly distributed.

Form the dough into two equal logs 3 inches / 7.5cm in diameter and 8 inches / 20cm long and place on the lined baking sheet. Leave about 3 inches / 7.5cm between them, so they have room to spread.

Bake in the middle of the oven for 30 to 35 minutes, just until the dough is set but still soft.

Allow the logs to cool, just until they are cool enough to handle, 10 to 15 minutes. With a sharp serrated knife, cut the logs into slices 1⁄2 inch / 1.3cm thick. Keep the oven on.

Lay the slices on the baking sheet and bake again for 10 minutes. Flip the cookies over and bake for about 10 more minutes, or until crisp.

Cool on baking sheet and store in an airtight container. These cookies last for weeks. Before serving, drizzle with melted chocolate and sprinkle with rose petals and a few flakes of salt (if using). Refrigerate for a few minutes until the chocolate is set.