In a 325° oven, in a pie pan, bake almonds until golden, about 8 minutes, stirring occasionally. Let cool.
In a food processor or bowl, mix flour and 1 T. sugar. Add 1/2 cup butter, cut into pieces (reserve remaining 1/4 cup butter for step #3). Whirl or rub with your fingers until mixture forms fine crumbs. Add 1 egg yolk; whirl or mix with a fork until dough holds together. Pat into a smooth ball, then firmly press dough over bottom and up sides of a 9-inch tart pan with removable rim.
In food processor (same one, no need to wash), whirl almonds and 1 cup sugar until nuts are finely ground. Add remaining butter and the whole eggs; whirl until smooth.
Peel and core apples; slice 1/8-inch thick. Overlap slices neatly in dough-lined pan. Pour nut mixture over fruit.
Bake in a 325° oven until crust is browned and apples are tender when pierced, 50 to 60 minutes.
In a 6 to 8-inch frying pan over medium heat, stir jam until melted; add liqueur. Spoon warm jam evenly over hot tart. Return to oven and bake until jam bubbles slightly, 3 to 5 minutes.
Let tart cool on a rack at least 30 minutes; remove pan rim. Serve warm or cooled off.