Russian Potato Casserole With Caramelized Onions

• 4 eggs to blend (beaten)
• 1 stick butter
• 1,100 gr russet potatoes
• 475 ml sour cream
• 240 ml cream (heavy)
• 240 ml sour cream
• 70 gr butter
• 60 ml olive oil
• 14 gr sugar
• 2 gr dill weed