Step 1

Whisk the sugar, water, milk and salt together in a medium saucepan. Bring the mixture to a simmer, stirring occasionally to dissolve the sugar. While the mixture is heating on the stove, whisk the egg yolks together in a large bowl.

Step 2

When the milk mixture has come to a gentle simmer, slowly stream it into the egg yolks while whisking constantly. Pour the mixture back into the saucepan and cook over medium low heat while whisking constantly until the mixture comes to 185ºF. Be careful not to let the mixture boil which will scramble the eggs and ruin the base.

Step 3

Remove the custard from the heat and chill completely. When you are ready to churn the ice cream, whisk in the olive oil. The mixture will be thick and glossy. Churn the custard in an ice cream machine according to manufacturer's instructions, adding the cacao nibs just before the ice cream is done spinning. Remove to a freezer safe container and freeze until firm, 4 hours or overnight.

Step 4

Melt the chocolate and butter together over a double boiler. Stir occasionally until the mixture is completely smooth. Remove from the heat and set aside while you prepare the rest of the cookies

Step 5

In the bowl of a standing mixer fitted with the whisk attachment or with an electric mixer, beat the eggs. Slowly add in the sugar and beat until the mixture is light in color and the eggs have tripled in volume.

Step 6

Stir in the vanilla extract, followed by the melted chocolate mixture. Finally, remove the bowl from the mixer and fold in the flour mixture until well combined. The dough will be very soft, almost batter-like in texture. Refrigerate the dough for about 30 minutes or until firm enough to scoop.

Step 7

Preheat oven to 350º. Line a baking sheet with parchment paper and portion the cookies into heaping tablespoons. Sprinkle each cookie with flaky salt and bake the cookies for 8-10 minutes or until the cookies have puffed and crackly tops. Let the cookies cool on the baking sheets for 5 minutes then move to a rack to cool completely.

Step 8

When the cookies have cooled completely and the ice cream is firm enough to scoop, assemble the sandwiches.

Step 9

To Assemble: Flip half of the cookies over so their flat sides are up. Top each cookie with a small scoop of ice cream (a cookie scoop makes a great mini ice cream scoop) and top the ice cream with another cookie, flat side down. Put the sandwiches on a parchment lined baking sheet or plate and re-freeze until firm.