From Ratio: The Simple Codes Behind the Craft of Everyday Cooking by Michael Ruhlman. Copyright © 2009 Scribner.

This is a basic vinaigrette only instead of being cold, it's mixed together in a medium hot pan, which intensifies the flavor of the tomato and the sweetness of the shallot.†This is a great sauce for white fish, halibut or cod or tilapia (and would do wonders for the ubiquitous boneless chicken breast).†But it also it works well with boiled new potatoes, salt cod, or a combination of boiled new potatoes, or other root vegetables, and salt cod or smoked trout.

• 1/2 cup seeded, diced tomato
• salt to taste (about 1/2 teaspoon)
• 1/4 cup sliced shallot
• 1 teaspoon minced garlic
• 1 tablespoon canola oil
• 1 ounce sherry vinegar (2 tablespoons)
• 1 tablespoon Dijon mustard
• 2 1/2†ounces olive oil (5 tablespoons)

â€

Toss the tomatoes with the salt to begin drawing out their moisture and flavor.†Sauté the shallot in canola oil over medium high heat until translucent.†Add the tomato and any liquid that's leached out to the pan and cook stirring for a minute or so to heat the tomato and reduce some of the liquid.†And the mustard and vinegar and stir to combine.††Whisk in the oil until incorporated then remove the pan from heat.†Taste for seasoning, add salt or vinegar as needed.†Spoon over chicken, fish or vegetables.