Preheat your oven to 400°F.

Make shortbread crust, using food processor OR pastry blender. Combine flour, sugar, salt and cold butter chunks in food processor OR large bowl. If using a food processor, pulse ingredients until combined and butter is size of peas. If using a pastry blender, cut butter into other ingredients until combined and butter is size of peas. Add egg yolks and mix, to combine. into a crumbly mixture.

Remove ¼ of crust mixture; set it aside. Take remaining ¾ of the mixture and pat it firmly into a 9" tart pan (with removable bottom disc). Firmly compact mixture with fingers (or bottom of a glass) to form a solid bottom crust and sides of the tart pan. When done, set aside.

Peel pears, cut them vertically in half, remove core; cut pears in thin slices. Place pear slices in large bowl; add pecans, brown sugar, flour, cinnamon and vanilla. Gently toss to combine. Carefully add pear filling to shortbread crust, mounding pears up in the middle of the pan.

Cover fruit with reserved topping. Use a spoon to sprinkle it over all fruit filling. TIP: When sprinkling topping around edges of crust, cup other hand around that section, to help hold streusel IN the tart. Use all topping to fully cover the tart.

Place foil on middle oven rack. Carefully place tart pan on foil. Bake at 400°F. for 15 minutes; then reduce heat to 350°F. Continue baking 25-30 minutes. Tart should be bubbly around edges and golden brown in color. Transfer tart pan to a wire rack to cool (in pan) for 15-20 minutes before removing sides of pan.

Remove tart from the pan by pressing up on the bottom disc (from underneath) and lifting up, to remove tart from the outer ring. Slice the pear pecan shortbread tart into eight wedges. Serve warm with vanilla ice cream, if desired!