I came across this soup on a trip to Amsterdam; where we had it at as a starter at a great little restaurant serving modern Dutch food. I ordered it, as I’m a big fan of mustard and was curious to see how a mustard soup would taste, especially as it was garnished with crayfish. The combination of the piquant mustard and the sweet little pieces of crayfish was a revelation. It’s been a while, but having been given some fantastic beer wholegrain mustard for Christmas, I finally got round to creating my own version of this soup the other day. No crayfish, but the salty bacon compliments the soup well and (it seems) is a traditional garnish.
You will need
1tsp butter
1 chopped onion
1 litre stock
125g crème fraiche
125g cream cheese
2tbsp wholegrain mustard
4tbsp cornflour/water mix
Crispy bacon and parsley to garnish
Melt the butter and gently sweat the onions until they are soft and translucent. Combine the crème fraiche, cream cheese and mustard. Add the stock to the onions and bring to the boil, before whisking in the mustard mix until smooth, then simmer for a few minutes. Add the cornflour mix, stir, and allow the soup to thicken Serve the soup with a sprinkle of crispy bacon bits and a bit of chopped parsley.
Spade Fork Spoon 
Now that sounds interesting. I wonder what stock you used? I’m thinking maybe a well-flavoured chicken stock to round out the sharp and salty flavours. I’ll be trying this very soon.
Yeah, chicken stock works a treat. Give it a go. It’s delicious. Thanks for commenting.
I had something like this in a cafe in Cornwall a few years ago. Think it was crab and mustard soup. Was very nice.
You should throw a few pots in your local river see if you get some crayfish to garnish your next lot. 🙂 apparently our rivers are full of them.
Hey, that’s a good point. Might have to do that. Or crab, as the restaurant in Cornwall served. Thanks.