Heat oven to 375 degrees. Have ready a 4-by-13- inch tart pan with removable bottom. On a lightly floured surface, roll out dough to an 8-by-16-inch rectangle, about 1/8 inch thick. Place dough in pan; gently press dough into pan. Trim dough flush with top of pan.Advertisement
Spread frangipane in an even layer on bottom of shell; chill shell 20 minutes.
Gently press plums into frangipane. Place tart on a baking sheet. Bake until frangipane is brown and crust is golden, about 45 minutes. Transfer to a wire rack to cool. Serve.