Combine the remaining 7 tablespoons butter, sweetener, and vanilla in a medium, heavy-bottomed, stainless steel saucepan. Heat over medium heat, stirring constantly, until the sweetener is fully dissolved, 6 to 8 minutes. Continue cooking, stirring constantly, just until the mixture reaches a deep brown/amber color then quickly remove the pan from the heat to avoid burning, 7 to 8 minutes.