Grilled Tri Tip Sandwich

My recipe for this Tri Tip Sandwich is so easy and crazy delicious! Filled with juicy and flavorful slices of grilled tri tip, melted cheese, thinly sliced red onions, and sandwiched between two thick slices of ciabatta, it's one of my favorite sandwiches!

Ingredients:

• 2 ½ teaspoons salt
• 2 ½ teaspoons black pepper
• 1 tablespoon garlic powder
• 2 ½ teaspoons smoked paprika
• 2 teaspoons onion powder
• 1 teaspoon minced rosemary

• One 2.5 pound tri-tip roast
• 1 tablespoon extra virgin olive oil

• ⅓ cup red wine vinegar
• ⅓ cup extra virgin olive oil
• 2 tablespoons whole grain mustard

• 4 ciabatta rolls, grilled/toasted or roll of choice
• 1 cup creamy horseradish sauce
• 1 cup sliced and lightly caramelized red onions
• 8 slices cheese