In a baked cheesecake, tart lemon juice is mellowed by the heat of the oven. For our Lemon Icebox Cheesecake, we needed to dial back the lemon juice to compensate. Lemon curd, a rich, tangy spread made from eggs, butter, cream, sugar, and lemon juice, added crisp lemon flavor without the undesirable “chew“ of zest or the processed flavor of lemon extract. Using lemon cookies instead of graham crackers for the crust created an additional layer of lemon flavor.

CRUST

• 10 lemon sandwich cookies, broken into pieces (about 1 1/4 cups)
• 2 tablespoons unsalted butter, melted
• 1 teaspoon grated lemon zest

CURD

• 1 large egg plus 1 egg yolk
• 1/4 cup sugar
• Pinch salt
• 2 tablespoons lemon juice
• 1 tablespoon unsalted butter
• 1 tablespoon heavy cream

FILLING

• 1 envelope (2 3/4 teaspoons) unflavored gelatin
• 1/4 cup lemon juice from 2 lemons
• 1 1/2 pounds cream cheese, cut into 1-inch pieces and softened
• 3/4 cup sugar
• Pinch salt
• 1 1/4 cups heavy cream, room temperature

1. MAKE CRUST Adjust oven rack to middle position and heat oven to 350 degrees. Process cookies in food processor until finely ground. Add butter and zest and pulse until combined. Press mixture into bottom of 9-inch springform pan. Bake until lightly browned and set, about 10 minutes. Cool completely on wire rack, at least 30 minutes.
2. MAKE CURD While crust is cooling, whisk egg, egg yolk, sugar, and salt together in small saucepan. Add lemon juice and cook over medium-low heat, stirring constantly, until thick and pudding like, about 3 minutes. Remove from heat and stir in butter and cream. Press through fine-mesh strainer into small bowl and refrigerate until needed.
3. SOFTEN GELATIN Combine lemon juice and gelatin in small bowl and let stand until gelatin softens, about 5 minutes. Microwave until mixture is bubbling around edges and gelatin dissolves, about 30 seconds. Set aside.
4. MAKE FILLING With electric mixer on medium speed, beat cream cheese, sugar, and salt until smooth and creamy, scraping down sides of bowl, about 2 minutes. Slowly add cream and beat until light and fluffy, about 2 minutes. Add gelatin mixture and ¼ cup curd, increase speed to medium-high, and beat until smooth and airy, about 3 minutes.
5. CHILL CHEESECAKE Pour filling into cooled crust and smooth top. Pour thin lines of remaining curd on top of cake and lightly drag paring knife or skewer through lines to create marbled appearance. Refrigerate until set, at least 6 hours. Remove sides of pan. Serve. (Cheesecake can be covered in plastic wrap and refrigerated for up to 3 days.)

Read more: http://community.tasteofhome.com/community_forums/f/30/t/853207.aspx#ixzz3SsUS3E42

Let the dissolved gelatin mixture cool down for a few minutes, or the gelatin will seize when combined with the filling. We tested our cheesecake with several store brands of lemon sandwich cookies; all worked well.