Preheat the oven to 350°F (180°C) and lightly grease or line two baking sheets with parchment paper.

In a very small bowl, dissolve the instant coffee in 1 teaspoon of hot water. Set aside.

In a large mixing bowl, cream the melted vegan butter, brown sugar, and salt using an electric mixer on medium speed until light and fluffy.

Add the vegetable oil, vanilla extract, and dissolved coffee to the creamed mixture. Mix on low speed until just combined (about 30 seconds).

Sift in the flour, cocoa powder, and baking soda. Stir with a spatula or spoon until mostly combined. Then fold in the chopped dark chocolate until evenly distributed. Do not overmix.

Scoop the dough and roll into 1½ tablespoon-sized balls. Place evenly spaced on the prepared baking sheets.

Bake for 11 minutes. The cookies will look soft in the center but will set as they cool.

Optional: Sprinkle with flaky sea salt immediately after baking, if desired.

Let the cookies cool on the baking sheets for 10 minutes, then transfer to a wire rack to cool completely.

If your cookies spread unevenly, use a round cookie cutter or glass (slightly larger than the cookie) to gently swirl them into perfect circles right after baking.