For the poached pears, combine apple juice, lemon peel, lemon juice, and ⅛ teaspoon salt in a large saucepan. Bring to a simmer over medium heat, add pears and increase heat to high. Bring liquid back to a simmer then decrease heat to low and cook, covered, until pears are fork-tender, about 10 minutes, turning pears halfway through. Remove from heat, and cool completely in liquid, uncovered.

For the whole-wheat tart crust, whisk together egg yolk, milk, and ½ teaspoon almond extract. Pulse 1¼ cup plus 2 tablespoons flour, confectioner’s sugar, and ¼ teaspoon salt in a food processor to combine, about 5 pulses.

Sprinkle 8 tablespoons butter over flour mixture and pulse until mixture resembles coarse crumbs, about 20 pulses. With processor running, add egg and milk mixture and process until dough comes together, 15–20 seconds.

Transfer dough to a work surface, form into a 6-inch disk, wrap in plastic wrap, and refrigerate at least 1 hour or up to 2 days. (Can be made up to 1 month ahead and frozen. Double wrap disk with plastic wrap before freezing. Let thaw 24 hours in refrigerator before using.)

For the almond filling, pulse almonds, granulated sugar, 1 tablespoon flour, and ¼ teaspoon salt in a food processor until as finely ground as possible. Add egg, egg white, ½ teaspoon almond extract, vanilla extract, and amaretto, process to combine, about 10 seconds.

Add 6 tablespoons butter and process until thoroughly combined. Transfer to a bowl, cover with plastic wrap, and chill at least 1 hour. (Can be made up to 2 days in advance, keep refrigerated.)

Remove tart dough from refrigerator and let stand at room temperature for 5–10 minutes until workable.

On a lightly floured surface, roll dough into a 12-inch circle, lifting and rotating occasionally to free from surface. Cut dough into 4 even squares, then transfer squares to four, 4½-inch diameter, mini tart pans with removable bottoms. Gently press dough into pans and up fluted sides, patch any holes or rips in dough. Trim overhang by running a rolling pin over each tart pan. Transfer dough-lined tart pans to a baking sheet and freeze at least 30 minutes.

Heat oven to 375°. Lightly spray four 6-inch square pieces of foil with nonstick cooking spray. Fit foil pieces, greased side down, tightly against each frozen tart shell, letting excess hang over sides. Fill foil-lined tart shells with dried beans or pie weights and bake until crusts are set and just starting to brown, 25 minutes. Remove foil and weights and bake crusts until dry and golden brown, another 5 minutes; transfer to a wire rack and cool completely.

Reduce oven temperature to 350°F. Remove almond filling from refrigerator and let stand at room temperature for 10 minutes. Line a plate or tray with paper towels, remove pears from poaching liquid and transfer to paper-towel-lined plate, pat dry with additional paper towels. Transfer pears to a cutting board and cut, lengthwise, into ¼-inch-thick slices.

Divide almond filling among cooled tart shells (heaping ¼ cup per tart) and spread into an even layer. Arrange pear slices on top of filling in a fan-like design, allowing slices to partially overlap. Bake tarts until filling is firm to the touch and crusts are deep golden brown, 40–45 minutes. Transfer to a wire rack to cool.

For the glaze, in a small saucepan over medium heat, bring jelly to a boil, stirring to remove lumps. Remove from heat and brush glaze on pears with a pastry brush.

If desired, dust with confectioner’s sugar to serve.