Heat oil in a large nonstick skillet over medium-high heat. Add 3/4 teaspoon salt, oregano, 1/4 teaspoon pepper, and potatoes; cook 10 minutes or until potatoes are browned, stirring occasionally. Remove from pan.
While potatoes cook, combine 1/2 teaspoon salt, 1/4 teaspoon pepper, fennel seeds, and garlic in a mortar. Mash to a paste with a pestle; rub over steak.
Heat a nonstick skillet coated with cooking spray over medium-high heat. Add steak; cook 3 minutes on each side or until desired degree of doneness. Thinly slice steak; serve with potatoes.