Preheat oven to 400F.
Heat oil in a 10-12 inch oven-proof skillet over medium heat, add the shallots. Saute, stirring occasionally, until shallot is golden brown, about 4 minutes.
Whisk eggs and cream together in a large bowl.
Combine with Dungeness crab and herbs. Season with salt and pepper.
Add butter to skillet. Pour egg mixture into the skillet.
Place in the preheated oven and bake 8 minutes.
Sprinkle minced preserved lemon on top of the frittata and bake additional 6-8 minutes or until set and golden brown. Let cool for 5 minutes.
Cut into six wedges, top with sour cream and salmon roe.