1. Preheat oven to 350°F. Set aside 8×8-inch baking dish. Prepare filling. Cut top stem and bottom butt off each pear. The bottom will give you a stable base to peel the pears. Using a small paring knife peel pears. Slice each pear in half. Using a small teaspoon to gently run down the length of the inside of pear, to remove fiberous spine, and scoop out seeds. Dice pears into hearty bite-size chunks and place in baking dish. Pour cranberries into dish. Top with sugar, cinnamon, and lemon juice. Toss lightly and set aside.
2. Next prepare topping. Whisk together flour, brown sugar, raw sugar, cinnamon, nutmeg, salt, and oats. Add unsalted butter and incorporate with your fingers. Work butter into topping mixture until well incorporated and some butter bits are still the size of oat flakes or small peas. Toss with nuts. Add about 1/3 of the topping mixture to pear and cranberry mixture. Toss to incorporate. Place remaining topping on top of the mixture.
2. Bake for 40-45 minutes, until bubbly and delicious smelling. Remove from oven and allow to cool for about 20 minutes before serving. This dish is perfect served warm with vanilla ice cream or a dollop of Greek yogurt for breakfast. Crumble lasts for up to 3 days, covered, in the fridge.