Baked Ginger-Apple Crumble

2 lb cooking apples (such as combination of Granny Smith and Golden Delicious), pared cored and sliced 1/4" thick
3 Tb. granulated sugar
1 Tb. chopped crystalline ginger
1/2 tsp. ground ginger
1 tsp. grated lemon zest
2 Tb. fresh lemon juice
1/3 cup Walnuts pieces
2/3 cup old-fashioned rolled oats
2/3 cup all-purpose flour
1/2 cup (packed) light brown sugar
1 tsp. cinnamon
Pinch salt
1/2 cup (1 stick) unsalted cold butter cut into 10 pieces
whipped cream or ice cream for serving

Preheat oven to 375 and butter 9 inch square baking pan
Toss apples with granulated sugar and both gingers add lemon juice and zest and toss again. Spread apples evenly in buttered pan./
Coarsely chop nuts and mix with brown sugar cinnamon and salt in mixing bowl.. Cut in butter with pastry blender until mixture resembles very course crumbs. (Or, coursely chop nuts in food processor, and dry ingredients and pulse several time to mix. Place butter on top and pulse several times to mix until mixture resembles very course crumbs). Srinkle topping over apples
Bake until apples are tender and topping is browned, 45-50 minutes. Serve warm with with whipped cream or ice cream.