Heat oven to 375°F. In 10-inch tart pan, unroll 1 pie crust; press in bottom and up side of pan. Trim along pan edge to remove excess crust. Set aside.
In large bowl, beat eggs, brown sugar, 3/4 cup maple syrup, the melted butter, flour and salt. Stir in apples and walnuts. Pour into crust-lined pan.
Make lattice top using remaining crust. Cut crust into 1-inch wide strips. Place half of the strips across filling in pie plate. Place remaining strips crosswise across first strips. Trim ends of strips; seal edges. Brush top with milk.
Bake 45 to 50 minutes or until golden brown. Cool completely. Serve with whipped cream; drizzle with additional maple syrup. Cover and refrigerate any remaining pie.