Put bacon on a parchment paper lined baking sheet. Cook in a 400 degree oven for 15 minutes. Check bacon and continue cooking for 2-5 minutes until crispy.
Drain on paper towels. Break into 1 inch pieces
While bacon is cooking, place dough in pie dish and pleat the edges
Spread the bottom of dough with mustard
Put onions in skillet with olive oil and butter and season with salt and pepper. Saute over medium low until caramelized, stirring occasionally, about 25 minutes.
Sprinkle with garlic and stir
Add ham and cook, stirring, for a minute or two, stir and turn burner off.
Add the spinach and cover pan. Let the covered pan sit for several minutes so the spinach will wilt down. Uncover and stir spinach into onion mixture.
Stir in artichoke hearts and corn.
Place half of mixture into pie dish. Sprinkle with half of cheese and bacon pieces. Repeat layers, ending with cheese. At this point dish can be covered and refrigerated for baking later if desired.
When ready to bake, beat eggs and add milk
Pour mixture slowly over the ingredients, letting it seep down into all the nooks and cranies.
Bake at 350 degrees for 60 minutes or until set in the center. Let rest for 15 minutes before slicing.