In a saucepan, combine heavy cream and whole milk. Heat over medium heat until it begins to steam.

In a separate bowl, whisk together egg yolks and sugar until pale and thick.

Gradually add the hot cream mixture to the egg yolks, whisking constantly.

Return the mixture to the saucepan and cook over low heat, stirring constantly, until it thickens and coats the back of a spoon.

Remove from heat and stir in vanilla extract. Let it cool completely.

Once the ice cream base is cool, fold in the cookie butter until well combined.

Churn the mixture in an ice cream maker according to the manufacturer's instructions.

Preheat a waffle cone maker.

In a bowl, whisk together eggs and sugar until well combined.

Add flour, melted butter, vanilla extract, and salt. Mix until smooth.

Pour a small amount of batter onto the waffle cone maker and cook until golden brown.

Quickly shape the waffle into a cone while it's still warm.