For the pear crumbles: Toss the pears, lemon juice, brown sugar, cinnamon, vanilla and 2 teaspoons of the flour together in a medium bowl. Divide the mixture between 3 mini pie plates.
Stir together the remaining 1/2 cup flour, oats, pecans, nutmeg, cloves and salt in a medium mixing bowl. Add the butter and, with fingers, blend it into the dry ingredients until fully incorporated. Squeeze the mixture into clumps, then divide it among the pie plates, spreading it to cover the pears.
Set the pie plates on a rimmed baking sheet and transfer to the oven. Bake until the fruit is bubbling and the crumble mixture is golden brown, about 35 minutes.
For the maple yogurt: Stir together the yogurt, maple syrup, orange zest and juice until well mixed.
Serve the warm crumbles with a dollop of the maple yogurt.
Any remaining maple yogurt can be kept refrigerated up to 3 days.