1/2 cup (1 stick) unsalted butter, cut into pieces
1 cup firmly packed light brown sugar
1/2 cup heavy cream or heavy whipping cream
Pinch of salt
1 tablespoon Scotch, brandy, or dark rum or 1 tablespoon pure vanilla extract
Combine the butter, brown sugar, cream, and salt in the slow cooker. Cover and cook on LOW for 1 hour.
Add the Scotch, whisking until well blended and heated through. Serve warm. You may keep the sauce warm on LOW for up to 1 hour before serving. If made in advance, store in the refrigerator in an airtight container for up to 1 week.