Boil a pot of water.
Add potatoes and cook until tender, 20-30 minutes. You should be able to pierce it with a fork.
In a mixer or with a hand mixer, beat potatoes until smooth.
Add orange juice, grated orange zest, Brandy, salt, pepper, 1/4 cup melted butter, 1/3 cup brown sugar and egg yolks. Beat until fluffy.
Pour into a 12" porcelain quiche dish or shallow pan.
Combine remaining ingredients (1/4 cup melted butter, 2/3 cup brown sugar, pecans and cinnamon).
Spread over the potatoes.
Cover and refrigerate overnight.
Bake on 350 for 45-50 minutes until brown and bubbly. Let stand for 10-12 minutes.