Add the water, sugar, and vanilla extract to a pot over medium-high heat and cook until the sugar dissolves.
Let the mixture sit and cool to room temperature, and add the syrup to an airtight jar or bottle. Store in the fridge.
For the espresso:
Dissolve the instant espresso powder in the hot water.
Alternatively, make your own espresso if you have an espresso machine, or use a french press to make espresso with ground espresso beans without a machine.
For the foamed milk:
Add the milk to a mason jar and shake very well to froth. Froth with a hand-held milk frother.
If you'd like a warm latte, heat the milk in a pot and froth with a hand-held frother.
Alternatively, froth the cold milk in an electric milk frother (if you have one) on the cold setting (or the hot setting if you'd like a warm latte), or simply shake the mason jar very well until everything is combined and a small layer of foam appears on the top of the milk.
To serve:
Pour the espresso (over ice, if desired) into each glass or mug.
Add 2 tablespoons of the simple syrup into each glass or mug.
Pour 1 1/2 cup of the milk over the espresso and ice into each mug or glass.
Notes
This recipe makes 2 servings (1 shot of espresso each, 1.5 cups of milk).The simple syrup recipe makes 8 tablespoons of simple syrup (or 1/2 cup), so feel free to add a little extra simple syrup to each serving depending on your tastes, or substitute with maple syrup if desired.To make this recipe low carb/keto, simply replace the simple syrup with a few drops of liquid stevia.For a warm latte, simple skip the ice and heat the milk in a pot on the stove just to a simmer, or in the microwave, before frothing.