Combine ground beef, cheese, jalapenos, salt, pepper, and mustard seeds in a large mixing bowl. Portion by hand into 42 "popper"-shaped balls, approximately 1 ounce each.
Crack and whisk eggs; put in a shallow dish. Combine bread crumbs and put in a second shallow dish.
Prepare a pot with frying oil; heat to 325 degrees F. Roll poppers in egg mix, 6 to 8 at a time. Roll in bread crumbs; repeat. Deep fry 4 minutes in batches. Allow to dry on paper towels.