1. Heat oven to 425 degrees F. Place 1-1/4 cups (about half) of the piecrust mix (reserve remainder for another recipe) in a medium-size bowl. Add cinnamon; stir with a fork to combine. Add 2 tablespoons ice water and stir until dough comes together in a ball.
2. Transfer dough to a floured surface; roll out to a 10-inch circle. Drape into a 9-inch fluted tart pan. Fit into bottom, then fold over edge to come halfway up side of pan. Pierce with a fork, and line with nonstick foil. Fill foil with pie weights; bake crust at 425 degrees F for 8 minutes.
3. While crust bakes, place egg white and salt in a medium-size bowl. Add 1/3 cup of the sugar (1 tablespoon at a time), beating constantly with an electric mixer. Once sugar is added, beat for 1 minute. Stir in almonds and 1 tablespoon flour.
4. Remove crust from oven and remove foil and weights. Spread almond mixture over bottom of crust. Set aside.
5. Peel apples, and cut away from cores. Cut pieces into 1/4-inch-thick slices. Toss slices in a large bowl with remaining 2 tablespoons sugar and remaining 2 teaspoons flour. Fan slices in two concentric circles in crust, packing as closely together as possible.
6. Bake tart at 425 degrees Ffor 30 to 35 minutes, until apples are knife-tender. Meanwhile, melt jelly in microwave, about 20 seconds. Stir until smooth. Brush jelly onto warm tart. Slice and serve.