Key Lime Tart

Ingredients

• 2 tablespoons butter chilled cut into small pieces
• 0.8 cup cake flour 
• 0.5 teaspoon apple cider vinegar 
• 0.3 teaspoon cream of tartar 
• 3 large egg whites 
• 4 large egg yolk 
• 2 tablespoons water 
• 0.5 cup juice of lime fresh ( 4 limes)
• 4 teaspoons lime zest grated
• 1 tablespoon olive oil 
• 1 Dash salt 
• 0.3 cup sugar 
• 0.5 teaspoon sugar 
• 14 ounce condensed milk fat-free sweetened canned
• 0.3 teaspoon vanilla extract 

Equipment

• food processor
• bowl
• frying pan
• baking paper
• oven
• knife
• whisk
• wire rack
• blender
• plastic wrap
• measuring cup
• tart form

Directions

1. To prepare crust, lightly spoon flour into dry measuring cups; level with a knife.
2. Place flour, 1/2 teaspoon sugar, and salt in a food processor; pulse 2 times or until combined.
3. Add butter and oil; pulse 5 times or until mixture resembles coarse meal.
4. Drizzle flour mixture with water and vinegar; pulse 10 times or just until combined. Gently press mixture into a 3-inch circle on plastic wrap, and cover and chill for 30 minutes.
5. Preheat oven to 42
6. Slightly overlap 2 sheets of plastic wrap on a slightly damp surface. Unwrap and place chilled dough on plastic wrap. Cover with 2 additional sheets of overlapping plastic wrap.
7. Roll dough, still covered, into a 10-inch circle. Fit dough, plastic wrap side up, into a 9-inch round removable-bottom tart pan.
8. Remove remaining plastic wrap. Press dough against bottom and sides of pan. Pierce bottom of dough with a fork. Line bottom of dough with a piece of parchment paper; arrange pie weights on paper.
9. Bake at 425 for 16 minutes or until edge is lightly browned.
10. Remove pie weights and parchment paper; bake an additional 5 minutes or until bottom of crust is lightly browned. Cool on a wire rack.
11. Reduce oven temperature to 35
12. To prepare filling, combine rind, juice, egg yolks, and milk, stirring with a whisk until well blended.
13. Pour into prepared crust.
14. Bake at 350 for 15 minutes or until set.
15. Remove tart from oven; place on a wire rack.
16. Increase oven temperature to 42
17. To prepare meringue, place cream of tartar and egg whites in a large bowl; beat with a mixer at high speed until foamy.
18. Add 1/4 cup sugar, 1 tablespoon at a time, beating until stiff peaks form; beat in vanilla.
19. Spread meringue evenly over filling, sealing to edge of crust. Make peaks with the back of a spoon (shown here).
20. Bake at 425 for 4 minutes or until golden brown.
21. Serve chilled or at room temperature.