Poached eggs with roasted portabellas and tomatoes

My new favorite Sunday brunch recipe, swiped from epicurious.com :). If you're looking for a total egg-poaching adventure, google Julia Child's instructions for how to poach the "proper" way. It's fun, I promise!

4 (3-inch-wide) portabella mushroom caps, stems discarded
2 plum tomatoes, halved lengthwise
3 tablespoons olive oil
1/2 teaspoon salt
1/4 teaspoon black pepper
1 teaspoon distilled white vinegar
4 large eggs
1/2 teaspoon balsamic vinegar
cheddar cheese
1 tablespoon finely chopped fresh chives

Preheat broiler.

Brush mushrooms and tomatoes with oil and sprinkle with salt and pepper. Arrange mushrooms, stemmed sides down, and tomato halves, cut sides up, on a broiler pan. Broil 6 inches from heat, turning over mushrooms halfway through cooking, until tender and tomatoes are slightly charred, about 7 minutes total.

While vegetables are broiling, fill a deep 10-inch skillet with 1 1/4 inches cold water. Add white vinegar and bring to a simmer.

Break 1 egg into a cup, then slide egg into simmering water. Repeat with remaining eggs, spacing them in skillet, and poach at a bare simmer until whites are firm but yolks are still runny, 2 to 3 minutes. Gently transfer eggs with a slotted spoon to paper towels to drain and season with salt and pepper.

Sprinkle stemmed sides of mushrooms with balsamic vinegar, then put 1 tomato half, cut side up, on each mushroom and top with an egg. Grate cheddar cheese on top and sprinkle with chives.