Mix the coarse salt, 2 Tbsps sugar and black pepper in a bowl. Position tenderloin on a generous piece of plastic wrap. Rub the tenderloin all over with the cut side of the garlic clove. Discard garlic.

Pat the salt mixture over the pork, coating it completely. Press 6 Tbsps of the dill all over the pork. Wrap tightly with the plastic wrap. Place tenderloin on a plate to catch any liquid and refrigerate at least 6 hours. (Can leave it up to 24 hours).

Preheat oven to 400 degrees. Remove wrap from tenderloin. Brush off a bit of the dill, and dry the tenderloin by patting gently with a paper towel.

Spray a baking pan and roast the pork to internal temperature of 150 degrees F. (About 25-30 minutes). Turn tenderloin half way through the roasting.

Allow tenderloin to cool completely, then cover and chill at least another 6 hours (or overnight).

Preheat oven to 350 degrees. Cut the baguette on a slight diagonal about ¼-1/3" thick. Brush both sides with olive oil. Place on baking sheet and bake 15 minutes, turning slices halfway through. Allow crostini to cool completely. Crostini can be made a day ahead and kept in an airtight container on counter.

Stir white vinegar and the remaining 4 Tbsps sugar in a bowl until sugar dissolves. You can do 30 seconds in the microwave after stirring well to help sugar to dissolve. Whisk in the mustard and remaining tablespoon of dill. (Can be made a day ahead.)

Cut pork tenderloin into ¼" thick slices. Place 1 slice of tenderloin on a crostini and drizzle with a bit of sweet mustard sauce. Can be assembled a couple of hours ahead and kept in the fridge.