Preheat your oven to 425°F (220°C). Spread the frozen tater tots in a single layer on a large rimmed baking sheet. Sprinkle them lightly with garlic powder, salt, and pepper. Bake according to the package instructions, usually for 20 to 25 minutes, until they are deep golden brown and very crispy. Flipping them halfway through ensures even browning.
Once the tots are crispy, remove the baking sheet from the oven. Carefully bunch the tots closer together so there are fewer gaps. Generously sprinkle the shredded cheddar cheese and the crispy bacon bits over the top of the hot tots.
Return the baking sheet to the oven for another 3 to 5 minutes. You want the cheese to be completely melted, bubbly, and just starting to brown at the edges. Watch closely to prevent the cheese from burning.
Remove the tray from the oven. Dollop small spoonfuls of sour cream across the top, or drizzle it over if you prefer a thinner consistency. Scatter the sliced green onions and pickled jalapeños over the melted cheese. Serve immediately while hot and crispy.