I grew up very close to my Dutch Grandmother who I called Oma and a few years ago I was lucky enough to go on the trip of a lifetime and travel by boat through out the entire country's canals. In a small northern town called Sneek, I stayed at a funky hotel that was similar to a hostel. Small rooms, shared bathrooms and a dark bar, restaurant and lobby all in one. After a long night of riding our bikes around town and drinking way to much amazing beer, I came back to the hotel to everyone eating soup that smelled like nothing I had smelt before. Mustard Soup! This is what I have come up with and I think its pretty close. —Danielle
In a Dutch oven over medium heat melt the butter. Add the leeks, garlic and a pinch of salt cook for 12-15 minutes until leeks are tender and light brown. Add the cup of beer to deglaze all the good bits off the bottom of the pan. Next into the pot all the greens and the stock. Bring to a slow boil and cover. Cook down the greens until tender about 7-10 minutes. Take pot off the heat. Using an immersion blender puree the greens until smooth. Be very careful not to splash its going to be very hot!
Once the greens are smooth return the pot back to medium heat and cook until it just starts to bubble. Stir in the mustard and the cubes of Brie until the cheese has melted and the soup has thickened. Season with more salt and white pepper to taste. Enjoy!