Baked German Pancake with Butter Syrup

Preheat the oven to 400 degrees F. Put two tablespoons butter in a glass 9X13-inch baking dish and pop the pan in the oven while it preheats (if it's taking a while to mix up the batter, keep an eye on the dish so the butter doesn't burn; take it out when the butter is melted).Combine the eggs, milk and vanilla in a blender and process on low speed until smooth, 10-20 seconds. Add the flour and salt and blend until just combined; the batter should be smooth but take care not to overblend or the pancakes may turn out dense and cakey.Take the preheated, buttered pan out of the oven and swirl the butter to coat the bottom of the pan. Pour the batter into the pan and immediately return to the oven. Bake for 20 minutes until the pancake is puffy and lightly browned on the bottom and edges.Serve immediately with jam, butter syrup, maple syrup or whatever else your heart desires.For the butter syrup, in a larger than you think saucepan (it will foam and triple in volume at the end), combine the sugar, buttermilk and butter and bring to a boil, stirring often. Reduce the heat and simmer for 7 minutes. Off the heat, stir in the vanilla and baking soda until well-combined. Serve warm over pancakes.