I got this recipe off America's Test Kitchen. It is the BEST pasta salad I have ever had, although I did tweak it a bit.
8 ounces sliced pepperoni cut in 1/4 inch strips
11 Tbsp red wine vinegar
7 Tbsp extra virgin olive oil
3 Tbsp mayonnaise
12 oz jar sliced pepperoncini*, 2Tbsp juice reserved
4 garlic cloves pressed
1/4 tsp red pepper flakes
1/2 tsp salt
1/2 tsp pepper
1 lb fusilli or campanelle
2 lbs white mushrooms quartered
1 1/2 C shredded provolone cheese
20-24 oz roasted red peppers, drained patted dry and chopped course
Put several paper towels on a plate. Put pepperoni strips on top and cover with several more paper towels. Put in the microwave for one minute. Set aside. Whisk 6 tablespoons of vinegar, olive oil, mayonnaise, pepperoncini juice, garlic, red, pepper flakes, salt and pepper in small bowl. Bring 4 quarts of water to boil in a large pot. Add 1 Tbsp salt and pasta and cook until al dente. Drain pasta, return to pot, and toss with 1/2 cup dressing and remaining vinegar. Spread pasta on rimmed baking sheet, and refrigerate until chilled. Meanwhile, bring remaining dressing to simmer in large skillet over med-high heat. Add mushrooms and cook until they release their juices and are lightly browned. Transfer to large bowl and cool. Add pepperoni, provolone, roasted red peppers, pepperoncini, and cooled pasta to mushrooms and toss well. Season with salt and pepper. Serve at room temperature. Salad can be refrigerated for up to 3 days.
*You can use the mild ones from vlasic, but you still need the juice from the real things to get a good tasting dressing. The real ones give a nice bite. I like to add a few of those and do the rest mild.