Grilled Flank Steak Sammies

Whenever I buy flank steak at Costco they often come two flank steaks to a package. If I'm planning to use the grill I often marinate and grill both and then freeze one for later. Flank steak makes really tasty sandwiches. This time I switched up the flavors and used bleu cheese.

1/2 small grilled flank steak, sliced thinly
1/2 large onion, sliced
pepper

3 large panini or hard rolls, sliced
some arugula
some bleu cheese
a little mayo
thin tomato slices

Sauté onion sliced in skillet for 8 minutes and then throw in the grilled flank steak just to warm it briefly.

On bottom half of roll spread some bleu cheese, then add some arugula, pile on some steak and onions and season with pepper, add a slice of tomato and top with other half (can add some mayo to the top if you wish).