Ingredients

3 tablespoons finely chopped red onion 

1 teaspoon Dijon mustard 

2 tablespoons red-wine vinegar 

1/4 cup extra-virgin olive oil 

1 3/4 cups cooked cannellini beans 

1/2 cup chopped fresh herbs, such as parsley, chives, and dill 

Kosher salt and freshly ground pepper 

Preparation

Soak onion in cold water, 10 minutes.

Meanwhile, whisk Dijon and vinegar in a bowl. Slowly whisk in oil until combined. Drain onion and dry well. Stir into dressing along with beans and herbs; season with salt and pepper. Let sit 15 to 20 minutes or refrigerate in an airtight container up to 5 days. Serve as a side, over meat and fish, on toasted rustic bread, or mixed into greens.