Meanwhile, cook the bacon in a wide skillet until browned on both sides. Remove to a paper towel to drain, then chop into strips.
Remove all but one tablespoon of bacon grease from the skillet and set over medium heat. Add the chopped onions and asparagus and cook until onions are softened but not browned, about 4 minutes.
Layer the bacon, onions, and asparagus into the parbaked pie shell. Scatter the chunks of cream cheese on top.
In a bowl, whisk together the eggs, cream, and salt and pour into the pie shell.
Place the pie on a sheet pan and bake until golden brown on top and center is set when jiggled, 30-40 minutes.
Cool completely before serving. Serve warm or at room temperature. To reheat, place in a 350 degree oven for 20-30 minutes. Leftovers should be stored in the fridge.