Preheat the oven to 350 degrees F.
Butter an 11-inch oval baking dish and sprinkle with Demerara sugar, tapping out any excess. Scatter the cherries over the bottom of the baking dish and set side.
Whisk the flour, sugar and salt in a medium bowl. In another bowl, mix together the milk, cream, butter, vanilla, eggs and lemon zest. Whisk the dry ingredients into the wet ingredients until just combined.
Pour the batter over the cherries. Bake until puffed and slightly golden on top, 30 to 35 minutes. Let cool for about 5 minutes. (The cake tends to fall slightly as it cools.)
Sprinkle some more Demerara sugar on top and serve while still warm. Spoon the cake out of the pan to serve.
Many think Demerara sugar is another kind of brown sugar, but that is not the case. Most brown sugar you find today is refined white sugar with a bit of added molasses. Demerara sugar is the result of the crystallization that occurs when processing cane juice into sugar crystals. The large crystals and caramel-like flavor make it an interesting option when baking desserts.