Preheat waffle iron.
Mix dry ingredients in a medium bowl.
Add buttermilk, oil and eggs; mix until smooth (with hand held mixer). It will rise as it sits for a minute. Do not stir down as you scoop out and into the waffle iron.
Spread onto hot waffle iron. (leave room around edge for batter to spread) You may want to spray or wipe the Teflon with an oily paper towel, just before cooking the first waffle. It should be fine then for the batch.
In a small pot, heat 2 cups milk until it begins to boil (medium heat).
While you are doing this: mix dry ingredients in a small bowl, add just a little of the reserved ½ cup of milk, blend the egg yolks in well, and then the rest of the ½ cup milk.
Stir mixture into the milk in the pot just as it begins to boil up (you will see skin forming) and stir with whisk until the sauce begins to bubble and thicken.
For raspberry sauce/syrup: Blend raspberries with sugar, stir and let sit for a few hours. Pour into small jars and freeze. Thaw just before serving.
