¼cupmaple syrup½ cup brown sugar can be substituted
¼cupapple sauce or 1 large apple*
2large eggs
¼teaspoonsalt
Instructions
Puree all ingredients together in a blender (you can also use a handblender if it's easier, or whisk as a last resort) then pour the mixture into a stainless steel mixing bowl of about 1.5 qt capacity.
Set the mixing bowl on top of a small pot filled with a few inches of water (the bowl shouldn’t touch the water).
Bring the pot to a simmer, turn the heat to low, then cook, stirring occasionally, until the mustard thickens, typically about 30 minutes.
Cool the mustard and refrigerate. Even though it contains cooked egg, the mustard will keep for weeks in the fridge due to the sugar and vinegar.
Notes
*To make this using an apple, peel and chop a baking apple into pieces, then puree in a blender with a cup of water and cook down to a paste, then proceed as directed.