In a medium mixing bowl, whisk together the rolled oats, almond milk, half of the Greek yogurt, chia seeds, one tablespoon of maple syrup, vanilla extract, and cooled espresso until well combined.

Divide the oat mixture evenly between two small mason jars or serving glasses, smoothing the top of each layer with a spoon.

In a separate bowl, stir together the remaining Greek yogurt, mascarpone cheese, and the remaining tablespoon of maple syrup until smooth and creamy.

Spoon the mascarpone topping evenly over the oat layers in both jars. Cover tightly with lids or plastic wrap and refrigerate overnight, or for at least 6 hours.

Just before serving, use a fine-mesh sieve to dust the tops generously with unsweetened cocoa powder.