Grilled Steak and Peppers Vinaigrette

Ingredients

• 2 tablespoons dijon mustard 
• 1 large bunch leeks white green (2 to 3 pounds; and pale parts only)
• 1.8 cups chicken broth reduced-sodium
• 2 tablespoons olive oil divided
• 5 tablespoons olive oil extra-virgin
• 4  cubanelle peppers green italian ( frying peppers)
• 2 tablespoons red-wine vinegar 
• 2 pounds sirloin flap steaks 
• 3  thyme sprigs 
• 1  turkish or 
• 2 tablespoons butter unsalted

Equipment

• bowl
• frying pan
• whisk
• grill
• grill pan

Directions

1. Halve leeks lengthwise and cut enough crosswise into 1-inch pieces to measure 8 cups, then wash.
2. Simmer leeks, butter, broth, bay leaf, thyme, 1/2 teaspoon salt, and 1/4 teaspoon pepper in a 12-inch heavy skillet over medium heat, covered, stirring occasionally, until leeks are very tender, about 20 minutes. Uncover and boil until liquid has reduced to about 2 tablespoons. Discard bay leaf and thyme.
3. Meanwhile, heat grill pan over medium-high heat until hot.
4. Brush steaks with 2 tablespoons olive oil and season with 1 teaspoon salt and 1/2 teaspoon pepper. Grill steaks, turning once, about 8 minutes total for medium-rare.
5. Transfer to a plate and let rest 15 minutes.
6. Meanwhile, halve and seed peppers and toss with remaining 2 teaspoon olive oil, 1/4 teaspoon salt, and 1/8 teaspoon pepper. Grill, turning once, until crisp-tender and lightly charred, 6 to 10 minutes total.
7. Cut crosswise into 1-inch pieces.
8. Whisk together vinegar, mustard, 1/4 teaspoon salt, and 1/8 teaspoon pepper in a medium bowl.
9. Add extra-virgin olive oil in a slow stream, whisking until emulsified.
10. Add peppers.
11. Serve steaks over leeks with their juices, drizzle with meat juices from plate, and top with peppers and vinaigrette.
12. mashed potatoes