Preheat the oven to 425°F (220°C). Fill a large pot with water, add a generous pinch of salt, and bring to a boil.

Wash the potatoes, pat them dry, and place them in the boiling water. Cook for 12–15 minutes until fork‑tender.

Drain the potatoes and let them cool enough to handle.

On a clean cutting board, press each potato with the heel of a fork or a butter knife until it flattens to about 1/2‑inch thickness.

Arrange the smashed potatoes on a baking sheet lined with parchment paper or a silicone mat.

Brush each potato with olive oil, then sprinkle minced garlic, salt, pepper, and optional red pepper flakes.

Dot each potato with a tablespoon of butter, sprinkle grated Parmesan, and scatter chopped parsley.

Bake for 20–25 minutes, flipping halfway, until the edges are golden brown and the tops are bubbling.

Serve immediately while hot and crispy.