For the sauce:
In a small saucepan, add the olive oil and heat. When the olive oil is hot, add the shallots and cook until softened. Add the chicken stock, beer, and molasses and cook until reduced by 75 percent, about 15 minutes. Season with salt and pepper.
For the warm potato salad:
In a large saute pan, add the olive oil and heat. Add the ham and onions and cook until the onions have softened. Add the garlic and saute for 1 minute. Add the potatoes and toss until heated through. Add the mustard and herbs, and season with salt and pepper.
For the tuna:
Season tuna with salt and pepper. In a small bowl, combine the horseradish, citrus zest, juice, and season with salt and pepper, and set aside. Brush one side of the tuna with Creole mustard. Press crust into mustard. Heat oil in a large saute pan. Add the tuna, crust side down, and sear until golden brown, about 3 minutes. Turn over and sear until medium rare, another 2 to 3 minutes.
Remove from the oven and drizzle with beer glaze and serve with warm potato salad.
Yield: 4 servings