Pimento Cheese with Fire Roasted Peppers

1 (8-oz) block mild or sharp Cheddar cheese, shredded 

1/3 cup mayonnaise

2 tablespoons cream cheese (1 ounce), softened

2 tablespoons chopped bottled fire-roasted red peppers or bottled diced pimento peppers

1 teaspoon grated sweet onion or 1/4 teaspoon onion powder

1/4 teaspoon salt

Crackers