Preheat oven to 425˚F. Line a sheet pan with parchment paper.
For the glaze:
Combine 2 tablespoons of melted butter and the maple syrup together in a small bowl. Set aside.
For the crumble:
Combine remaining melted butter, flour, chopped walnuts, brown sugar, cinnamon and salt in a medium-size bowl. Stir with a fork until ingredients are combined and wet crumbles form. Set aside.
For the pears:
Cut pears in half and carefully cut off any stems at the top. Remove the cores with a small thin edged spoon or a melon baller. Slice the pears fairly thin vertically, stopping ¼-1/2 inch from the stem end. (The pear slices should stay attached at the stem end.)
For the galette:
Place pie crust on a lightly floured work surface. Roll to a 13-inch circle. It’s okay if it’s not a perfect circle. This is a rustic tart. Fold crust in quarters and transfer to prepared sheet pan.
Arrange the pears decoratively on top of the pie crust, fanning them out to lie fairly flat. Leave a 1½-inch border of crust around the perimeter. Cut pears in half vertically if necessary to make them fit. Brush the pears with half of the reserved butter/syrup mixture then sprinkle with 1-2 tablespoons of sugar (depending on how sweet your pears are). Set remaining butter syrup mixture aside.
With your hand, sprinkle crumble mixture into crevices between pears and into any open areas along the perimeter of the pears. Try to keep most of the sliced pears exposed for a pretty presentation.
Fold the edges of the dough up and over the filling, pleating edges when needed. The center should remain open.
Place in preheated oven and bake for 20 minutes. Remove from oven and slowly brush all over with the remaining butter/syrup mixture. Return to oven for another 5-10 minutes, or until crust is golden and glazed.
Notes
See Café Tips above for more detailed instructions and tips.