STUFFED NICOISE TOMATOES

1/2 medium red onion, cut 1/4-inch slices
1 teaspoon plus 1 tablespoon olive oil, divided use
2 teaspoons salt (or to taste)
freshly-ground black pepper (to taste)
8 fingerling potatoes or other small potatoes (about 1/2 oz each)
6 beefsteak tomatoes (12 oz each)
1/4 cup capers, rinsed
4 ounces arugula, chopped
4 teaspoons black olive paste
1/4 cup Nicoise olives, halved
1 teaspoon fresh lemon juice
1 teaspoon balsamic vinegar
2 cans white tuna in oil (6-oz each), drained

Heat grill to medium hot.

Brush the onions with 1 teaspoon olive oil, and sprinkle to taste with salt and pepper. Cook on the grill until soft and golden, 3 to 5 minutes per side. Remove from grill, and let cool. If you don't have a grill, cook onions under a hot broiler.

Meanwhile, fill a medium saucepan with cold water, and add salt and potatoes. Set pot over high heat, and bring to a boil. Reduce heat; simmer until potatoes are fork tender, 10 to 14 minutes. Drain potatoes, let stand until cool enough to handle, and rub off as much skin as possible.

Trace a circle with the point of a knife extending about 1 inch beyond edges of tomato core. Using a sharp knife held on a diagonal, cut along circle, removing core in one cone-shaped piece; discard.

Slice the potatoes into long halves or quarters, depending on size and type used. Combine the onions, potatoes, capers, arugula, olive paste, olives, remaining 1 tablespoon olive oil, lemon juice, and balsamic vinegar in a large mixing bowl; toss. Crumble in the tuna, and toss gently. Adjust the seasoning to taste with salt and pepper.

Season the cavity of each tomato with salt and pepper. Fill each tomato with tuna mixture. These will hold well at room temperature for about 1 hour.

Servings: 6
Source: Martha Stewart Living Magazine, Jul/Aug 1997