Add the sugar, cream of tartar, and beer to a large heavy-bottom saucepan, stir until the sugar is dissolved, stop stirring.
Boil until a dark amber, about 8 minutes, swirling the pan occasionally if hot spots develop.
Remove from heat, stir in the heavy cream, vanilla, salt and butter until melted.
Add to a storage container, allow to cool until room temperature.
Make the ice cream:
Add the milk, vanilla, and cream to a pan over medium-high heat. Cook, stirring frequently until the milk starts to bubble around the edges. Remove from heat.
Add the yolks to a mixing bowl with the sugar. Stir until well combined.
Slowly add the milk mixture while whisking continuously.
Pour back into the saucepan over medium heat. Whisk constantly until the mixture has thickened slightly and coats the back of a spoon.
Add to an airtight container, stir in ½ cup caramel sauce. Refrigerate until chilled, about 3 hours.
Add to an ice cream maker, churn according to manufactures specifications until a soft-serve consistency (in a KitchenAid ice cream maker, this takes about 15 minutes).
Transfer to a freezer container, freeze until set, about 2 hours.
Add generous scoops of ice cream in between two stroopwafels, sandwich them together.
Freeze until ready to serve.
Notes
*cream of tartar is optional but it does prevent crystallization, if grainy caramel has ever been an issue for you.