Wash and dry the spinach leaves if using fresh. Pinch off any tough stems and roughly chop the spinach.
Heat the olive oil in a medium skillet over medium heat. Cook the spinach until wilted, about 3 minutes. Remove from the pan and place in a strainer to drain.
Reduce the heat to medium low and add the onion and butter to the skillet. Cook for 3 to 4 minutes or until tender.
Add the cream cheese and stir until melted.
Whisk in the heavy cream, garlic powder, and salt. Simmer 1 to 2 minutes or until thickened.
Gently squeeze any excess liquid from the spinach and stir it into the cream sauce. Taste and season with additional seasoned salt and pepper.
