Blended Coffee Frappé (Frappuccino-Style)

Before you start

A coffee-shop blended frappé is smooth, thick and stays that way for a while. Most homemade versions do not. Within minutes they separate into a layer of watery coffee under a cap of icy slush. The difference is a small amount of thickener in the commercial base, which holds the ice crystals and liquid together. At home, a pinch of xanthan gum does the same job.

The other decisions are about strength and temperature. Ice dilutes blended coffee more than any other drink, so the coffee must be strong and cold: chilled espresso, cold brew concentrate, or coffee frozen into cubes. Use a ratio of roughly one part liquid to one part ice by volume. More ice and the drink turns grainy and hard to blend; less and it is just cold milk.

Ingredients

• 90 ml (3 oz) cold brew concentrate or chilled espresso — strong, not regular-strength coffee
• 120 ml (4 oz) cold whole milk
• 30 ml (1 oz) simple syrup or flavored syrup
• ⅛ tsp (about 0.3 g) xanthan gum — optional but keeps the drink from separating
• 1½ cups (about 220 g) ice cubes
• to taste whipped cream and caramel or chocolate sauce — optional

Method

1. Pour the cold coffee, milk and syrup into the blender jar. Liquids go in first so the blades can move freely.
2. Sprinkle the xanthan gum over the liquid. Use only the amount listed; a little more makes the drink slimy.
3. Add the ice on top. Secure the lid.
4. Blend on low for 5 seconds to break up the ice, then on high for 30 to 40 seconds, until there are no audible chunks of ice and the mixture is thick and pourable. Stop and push the ice down with a tamper or spatula if it bridges above the blades.
5. Pour into a tall glass. It should mound slightly and hold its shape for a few seconds.
6. Top with whipped cream and a drizzle of sauce if you like, and serve with a wide straw.

Tips for success

• Freeze coffee in an ice cube tray and use it in place of half the ice. The drink stays strong as it blends.
• Xanthan gum is sold in the baking aisle. A small bag lasts for hundreds of drinks.
• Cold dulls sweetness, so a blended drink needs more syrup than a hot latte. Taste before pouring and add 10 ml if needed.

Substitutions

Xanthan gum

A tablespoon of instant vanilla pudding mix also thickens and stabilizes, while adding sweetness and vanilla. Without any thickener, drink it within a few minutes.

Whole milk

Oat milk blends creamy and smooth. Skim milk makes an icier drink. Half-and-half gives a very rich, milkshake-like texture.

Cold brew concentrate

2 tsp instant espresso powder dissolved in 30 ml cold water plus 60 ml extra milk is a quick, very convenient base.

Variations

Mocha frappé

Add 20 ml chocolate sauce and reduce the syrup to 15 ml.

Caramel frappé

Use caramel syrup, and drizzle caramel sauce inside the glass before pouring.

Troubleshooting

The drink separates into ice and liquid

There is no stabilizer, or it sat too long. Add the pinch of xanthan gum and serve right after blending.

It is chunky with ice

Too much ice for the liquid, or a weak blender. Add 30 ml more milk and blend longer, starting on low.

It tastes weak and watery

Regular-strength coffee was used. Use a concentrate, chilled espresso or coffee ice cubes.

Storage

Serve immediately. A blended frappé melts and loses its texture within 10 to 15 minutes, even with xanthan gum, and cannot be refrozen well. Leftover cold brew concentrate keeps sealed in the fridge for about a week.