1. Heat the milk: In a saucepan over medium heat, warm the milk until steaming (do not boil). Remove from heat.
2. Whisk yolks & sugar: In a bowl, whisk egg yolks and sugar until pale and slightly thickened.
3. Add dry ingredients: Sift in flour and cornstarch. Whisk until smooth.
4. Temper the eggs: Gradually pour hot milk into the yolk mixture, whisking constantly to prevent curdling.
5. Cook the custard: Pour mixture back into the saucepan. Cook over medium heat, stirring constantly with a wooden spoon or silicone spatula, until thickened and bubbling (5–7 minutes).
6. Add flavor: Remove from heat. Stir in lemon zest, lemon juice, butter, and vanilla. Mix until smooth and glossy.
7. Strain (optional): For ultra-smooth texture, strain through a fine-mesh sieve.
8. Cool properly: Transfer to a bowl. Press plastic wrap directly onto the surface (prevents skin). Chill at least 2 hours before using.

✨ Uses:
• Fill cream puffs, éclairs, or tart shells
• Layer in trifles or parfaits
• Spread between cake layers
• Serve chilled in glasses with berries

💡 Make ahead: Stores in the fridge up to 3 days. Stir before using.

PREP TIME & NUTRITION :
Prep Time : 10 mins , Cook Time : 10 mins , Total Time : 2 hrs 20 mins (includes chilling) , Servings : 2 cups (about 8 servings) , Calories : 140 per ¼-cup serving , Net Carbs: 16g , Fats: 8g , Protein: 3g