1. Place the rack in the middle of the oven and preheat to 175 °C (350 °F).
2. In a bowl, mix the rolled oats, maple syrup, and oil.
3. Divide the mixture into six removable-bottom tart pans with a diameter of 7.5 cm (3 in.) or eight muffin trays. Press down with the back of a small spoon to cover the pan walls.
4. Place the tarts on a baking tray and bake in the centre of the oven for 15 minutes or until the edges begin to brown slightly. Let cool for 10 minutes on a cake rack.
5. Garnish the tarts with 60 mL (¼ cup) of Greek yogurt and berries.

Chef’s secret: You can prepare the tart shells the day before and garnish the following morning.