Pour the 1/4 cup olive oil into a medium skillet and add about 15 whole garlic cloves.
Cook over low heat until the garlic is soft and golden brown, about 20 minutes, stirring every 4–6 minutes to prevent burning.
While the garlic cooks, trim excess fat from the steaks and cut into 1-inch pieces. Season evenly with 1/2 teaspoon salt and 1/2 teaspoon black pepper.
Press or mince the remaining 5 garlic cloves and set them aside.
When the slow-cooked garlic is soft and golden, remove the garlic cloves from the pan and reserve the garlic and the oil; drain off excess oil, leaving about 1 tablespoon in the skillet.
Heat the skillet over high heat. Once the oil is hot, add the steak pieces in a single layer (work in batches if needed) and sear 2 minutes without stirring.
Flip the steak pieces and cook 1 more minute, then add the reserved minced/pressed garlic and stir continuously for about 1 minute until fragrant.
Remove the steak from the skillet, toss with the reserved golden garlic and chopped parsley, and serve immediately.