Crock Pot Cheesy Salsa, Black Bean and Corn Dip

1 (15.5 oz) jar TOSTITOS® Medium Chunky Salsa

1 (15.5 oz) can black beans, drained and rinsed

1 (15.25 oz) can whole kernel corn, drained

½ cup (4 oz) cream cheese

½ cup light sour cream

2 cups shredded Monterey Jack and Cheddar cheese blend or Mexican cheese blend

TOSTITOS® Scoops, for serving

sliced green onions, for serving, optional