Steam the mixture: Add milk, apple cider and instant coffee granules to a small saucepan. Give it a stir and let it heat up until just before it’s simmering. Add vanilla extract and, if using, additional sweetener of choice.
Prepare mugs: Prepare the mugs by pouring salted caramel sauce into them and swirl to cover the bottom.
Blend the mixture: Cool the mixture a bit (unless you have a heat-proof blender) and then blend. It will get bigger in volume as you blend, so you shouldn’t completely fill the blender. Work in batches if needed.
Divide the mixture: Using a spoon, hold the foam back while you divide the milk mixture among the mugs. Then divide the foam between the mugs. Drizzle with more salted caramel sauce!