Iced coffee shake in a portable blender
About 3 minutes, once the coffee is cold · 1 bottle (350 ml)
A blended iced coffee is three ingredients and half a minute, with one rule that matters more than the recipe: the coffee has to be cold before it goes in. A sealed bottle and hot liquid are a bad combination, and the drink is worse for it anyway.
Ingredients
- 120 ml cold coffee — a double espresso, filter or instant
- 150 ml cold milk
- 1 small frozen banana, in slices
- Optional: a pinch of cinnamon, or 1 heaped tsp cocoa
Step by step
- Chill the coffee. Make the coffee ahead and refrigerate it, or brew it double strength over ice. Do not put hot liquid in a sealed bottle.
- Liquids first. Pour the cold coffee and the milk into the empty bottle.
- Frozen banana on top. Add the frozen banana slices over the liquid. They chill and thicken the drink better than ice does.
- One cycle. Seat the bottle on the base and double-click for a single 30-second cycle.
- Stop before it foams. Run a second cycle only if the banana is still in pieces. Coffee foams easily and over-blending fills the bottle with air.
Cold coffee, no exceptions
Hot liquid in a sealed bottle builds pressure as it is agitated, and a cap that has to be opened against pressure is a mess waiting to happen. Beyond the practical point, blending hot coffee with milk and ice gives you a lukewarm drink that is neither one thing nor the other.
The simplest route is to make the coffee the night before and leave it in the fridge. A double espresso, a mug of filter, or a cup of instant all work — this is not a recipe that rewards expensive coffee, because the milk and the cold flatten the differences.
Getting coffee cold in a hurry
If you did not plan ahead, brew it at double strength into half the water and pour it over ice. The ice melts into the gap you left, and you end up with cold coffee at normal strength rather than a watery cup.
A shallow bowl in the freezer for ten minutes also does it. What does not work is adding a lot of ice to hot coffee in the bottle — you get a warm, weak drink and a bottle that is too full.
The blend
Coffee and milk into the bottle first, then the banana or the ice on top. Seat the bottle and double-click for one 30-second cycle. With cold ingredients that is all it takes.
Frozen banana is better than ice here. It chills the drink, thickens it, and takes the edge off the coffee without needing sugar — and unlike ice it does not water the drink down as it stands.
Sweetening and flavouring
If you take sugar in coffee, add it to the coffee while it is still hot so it dissolves. Sugar added cold to a blended drink stays gritty at the bottom no matter how long you blend.
A pinch of cinnamon or a drop of vanilla suits it. A heaped teaspoon of cocoa turns it into something closer to a mocha, but add it with the liquid rather than on top, or it cakes on the blades.
Making it a protein coffee
A scoop of vanilla or chocolate protein powder works well here, and coffee hides the flavour of a powder better than fruit does. Keep the same order — liquid, then powder, then banana — and reduce the milk to 100 ml, because a scoop of powder plus a banana plus 150 ml overfills the bottle.
Blend for one cycle, check, and only run a second if you added frozen banana. Coffee foams readily and an over-blended coffee shake is mostly head.
Cleaning up
Coffee stains plastic over time, and milk residue is what makes a bottle smell. Rinse immediately, every time, rather than at the end of the day.
Warm water with a drop of dish soap, one 30-second cycle, then unscrew the base and rinse the blade side. Dry the halves separately.