Mixed Apple Pie with Hazelnut Crumb Crust and Maple Cream

Name: Mixed Apple Pie with Hazelnut Crumb Crust and Maple Cream
Ingredients: For the pie; 1 cup old-fashioned oats; 1/2 cup flour; 1/4 teaspoon salt; 1 teaspoon cinnamon; 3/4 cup toasted hazelnuts, finely chopped; 1/2 cup butter, melted; 6 cups mixed apples, cut into 1/4-inch slices (I like a blend of Golden Delicious, Jonathan, and Northern Spy); 3 tablespoons fresh lemon juice, plus 1/2 teaspoon zest; 1/4 cup maple syrup; 1/2 teaspoon allspice; 3/4 cup flour, plus 3 tablespoons; 1/2 cup brown sugar; 5 tablespoons cold butter, cut into 1/2-inch cubes; For the tangy maple cream; 1/2 cup heavy whipping cream, chilled; 1/2 cup plain Greek yogurt; 1 teaspoon maple extract OR maple syrup