Flank Steak with Cheesy Waffle Hash Browns

Name: Flank Steak with Cheesy Waffle Hash Browns
Ingredients: 2/3 c. olive oil; 1/4 c. red wine vinegar; 1 c. chopped mixed fresh herbs (basil, mint, cilantro and/or parsley); 1 garlic clove, finely grated; 1 serrano chile pepper, seeded and finely chopped; 1/2 shallot, chopped; 1/2 tsp. kosher salt; 1 30-ounce bag frozen, shredded hash brown potatoes, thawed; 1 c. shredded pepper jack cheese; 6 tbsp. salted butter, melted; 1 tbsp. kosher salt; 1/4 tsp. black pepper; Cooking spray; 1 1/2 lb. flank steak; Kosher salt and black pepper, to taste