The best dill-mustard sauce

I've posted a recipe for this before, but since then, I've found a better recipe. It comes from a book called The Swedish Smörgåsbord, by Gert Klötzke and Niclas Wahlström, who are also the chefs in charge of the christmas buffet at Fjäderholmarnas Krog which happens to be the very best there is, in my opinion.

I use the Kitchen-Aid for this. It makes quite a bit, so I divide it into separate containers at once, and just add dill when serving, since the dill doesn't hold up too well. The sauce, without dill, will keep for at least a few weeks in the fridge.

The best dill-mustard sauce
100 ml Swedish mustard - I use a mixture of coarse, strong, normal and sometimes even a little Dijon.
100 ml sugar
4 tbsp white wine vinegar
200 neutral oil (I use canola)
1tbsp honey
1 tsp salt
2-3 tsp cold coffee
200 ml finely chopped dill

Mix the mustard with the sugar and the vinegar. Add the oil while whisking, like you would while making any emulsion - drop by drop at first, then quicker. When all the oil is added, and your sauce is nice and smooth, season it with the honey, coffee and salt. Taste to see if you want more seasonings.

Just before serving, stir in the dill.