Heat oven to 400°F.
Butter a 9 inch tart pan.
Sprinkle with sugar.
Tap out excess sugar. Set aside.
Combine milk, eggs, egg yolks, butter, vanilla, lemon zest, sugar, and flour in blender.
Purée until smooth.
Allow to sit for 30 minutes.
While batter is resting, cut and pit apricots.
Place cut side up in prepared pan.
Pour batter over apricots.
Bake for 35 minutes, or until set.