01 - Preheat oven to 425°F. Cut potatoes into even fry-shaped strips. Toss with vegetable oil, smoked paprika, and salt until evenly coated. Spread in a single layer on a baking sheet. Bake for 25 minutes, flipping halfway through, until golden brown and crispy. Alternatively, bake frozen fries according to package instructions.
02 - Place sirloin strips in a mixing bowl. Drizzle with olive oil and season with garlic powder, black pepper, salt, and chili flakes. Toss to coat evenly and let marinate while the fries bake.
03 - Heat a large skillet over high heat until smoking. Add steak strips in a single layer, working in batches if needed. Sear for 1 to 2 minutes per side until a deep golden crust forms but the interior remains juicy. Transfer to a plate and rest for 2 minutes.
04 - In a small bowl, whisk together mayonnaise, Dijon mustard, ketchup, and lemon juice. Season with salt and pepper to taste. Adjust consistency with a splash of water if needed.
05 - Divide crispy fries among four bowls. Arrange steak strips over the fries. Top with sliced red onion, halved cherry tomatoes, diced avocado, and chopped parsley. Drizzle generously with the prepared sauce. Serve immediately while the fries are still hot and crisp.