Prepare the yams

• Scrub the sweet potatoes clean under running water.
• Peel them and cut into slices.

Make the glaze

• In a bowl, combine the dark brown sugar, granulated sugar, cinnamon, vanilla extract, maple syrup, lemon zest and lemon juice.

Arrange and coat the yams

• Arrange the sliced yams in the baking dish.
• Pour the glaze over the yams.

Add the remaining glaze

• Top with more dark brown sugar, the butter and more cinnamon.

Bake covered

• Cover the dish and bake at 190 °C.

Bake uncovered

• Bake uncovered until the yams are tender.