This super-easy potluck side comes together in just 20 minutes and is a huge hit at parties from summer to the holidays. 
Directions
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WHISK oil, vinegar, mustard, garlic, oregano, salt, and crushed red pepper in a large bowl.
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ADD broccoli florets and diced red onion, and gently massage the broccoli so it softens the slightest bit. Let sit for 15 minutes.
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ADD diced cheddar, salami, and peperoncini. Mix to combine well.