Line an 8-inch square pan with aluminum foil extending 2 inches beyond sides of pan. Grate 1 teaspoon zest from a lemon and squeeze 3 tablespoons juice. Beat butter, salt, 1/2 teaspoon lemon zest, and 1/4 cup sugar until creamy. On low speed, beat in flour until crumbly. Beat about 1 tablespoon lemon juice in until dough just holds together. Press dough into bottom of prepared pan. Refrigerate 15 minutes. Heat oven to 350 degrees. Bake crust until golden, 20 to 25 minutes.
Beat cheese and 2/3 cup sugar until smooth. Beat in eggs, 1/2 teaspoon lemon zest, and 2 tablespoons lemon juice. Pour over crust. Bake until firm and top puffs, 35 to 40 minutes. Refrigerate until cold. Let stand at room temperature 1 hour before cutting. Lift out of pan using foil as handles. Cut into triangles.
