What type of cheese is in American blue cheese dressing?

The ingredients are pretty simple for basic bleu Cheese Dressing

Mayonnaise

Half and Half

Heavy Cream

Blue Cheese Crumbles

2c. mayo

1c. Half and Half

1/2c. Heavy Cream

1 1/2c. Bleu Cheese Crumbles

Mix Half and Half and 1/2c. bleu cheese in blender or food processor. Blend until smooth. Add in heavy cream and mayo, blending until just blended. Stir in the remaining bleu cheese.

Play with the ingredient amount if you choose.