Begin by boiling the baby potatoes in a large pot of salted water for about 15-20 minutes, or until fork-tender. Drain and let cool slightly.
While the potatoes are cooling, heat a large skillet over medium-high heat. Add 2 tablespoons of butter and let it melt.
Season the steak cubes with salt and pepper. Once the butter is hot, add the steak to the skillet in a single layer. Cook for about 3-4 minutes, stirring occasionally, until browned and cooked to your desired doneness.
Add the minced garlic to the skillet and cook for an additional 1-2 minutes, stirring frequently. Remove from heat and stir in the remaining 2 tablespoons of butter until melted. Garnish with fresh parsley if desired.
While the steak is cooking, prepare the smashed potatoes. Place the boiled potatoes on a baking sheet lined with parchment paper. Use a fork or potato masher to gently smash each potato until flattened but still intact.
In a small bowl, mix together the shredded cheddar cheese, sour cream, milk, garlic powder, and salt and pepper to taste. Spoon this mixture over the smashed potatoes.
Preheat your oven to 400°F (200°C). Bake the smashed potatoes for about 15-20 minutes, or until the cheese is melted and bubbly.
Serve the garlic butter steak bites alongside the cheesy smashed potatoes for a delicious meal.