Instant in as much as it uses freeze dried coffee granules. Not actually any quicker than using an espresso machine and milk steamer but a good substitute if don't have one. Not the most complex process but as the only other people I know who do this are related to me I thought I'd share it.
Step 1: Heat a Mug of Milk
I zap it in a microwave for 90 seconds. If you prefer you can heat it in a sauce pan on the stove. I've been told in the past that I shouldn't microwave milk as it produces nurotoxins but as I'd been doing it for years with no ill effects and have kept doing so and am still healthy I figure it's either not true, very weak or I'm immune to it.
Step 2: Add Coffee Granules
place coffee granules in milk (they won't sink) if you want to add sugar do it now sprinkle it over the coffee granules. Then stir vigorously
Step 3: Let It Stand
just let it sit until the movement has almost stopped (30 to 60 seconds)
Step 4: Crush & Stir
not all the granules will have dissolved especially if you wanted it strong and have used 2 tea spoons of granules. draw any clumps to the edge of the mug and crush them with the back of the spoon. stir it again and it's ready to drink.