Bake sweet potatoes until tender in preheated 350°F oven 1 hour or, pierce sweet potatoes several times with fork and place on microwavable plate.
Microwave at HIGH (100% power) 16 to 18 minutes, rotating and turning over after 9 minutes.
Let stand 5 minutes.
While sweet potatoes are hot, cut lengthwise into halves.
Scrape hot pulp from skins into large bowl.
Beat 14 cup butter and 2 tablespoons sugar into sweet potatoes with electric mixer at medium speed until butter is melted.
Beat in eggs, orange juice, 1 1/2 teaspoons cinnamon, salt and nutmeg, scraping down side of bowl once.
Beat until smooth.
Pour mixture into 1 1/2-quart baking dish; smooth top.
For topping, combine flour, oats, remaining 1/4 cup sugar and 1/2 teaspoon cinnamon in medium bowl.
Cut in remaining 1/4 cup butter with pastry blender or 2 knives until mixture becomes coarse crumbs.
Stir in pecans.
Sprinkle topping evenly over sweet potatoes.
Preheat oven to 350°F Bake 25 to 30 minutes or until sweet potatoes are heated through.
For a crisper topping, broil 5 inches from heat 2 to 3 minutes or until golden brown.
Garnish, if desired.