Ingredients:

• 1-1/2 cups (375 mL) all-purpose flour
• 1/4 tsp (1 mL) salt
• 1/4 cup (50 mL) cold butter, cubed
• 1/4 cup (50 mL) lard or cold butter, cubed
• 1 egg yolk
• 1 tsp (5 mL) vinegar
• Ice water

Filling:

• 6 slices bacon
• 1 onion, finely chopped
• 1/2 tsp (2 mL) pepper
• 1/4 tsp (1 mL) salt
• 4 eggs
• 1/2 cup (125 mL) milk
• 1/4 cup (50 mL) 6% cream
• 2 tbsp (25 mL) dijon mustard
• 3/4 cup (175 mL) shredded Gruyère cheese

Preparation:

1. In large bowl, whisk flour with salt. Using pastry blender or 2 knives, cut in butter and lard until mixture resembles fine crumbs with a few larger pieces. In liquid measure, whisk egg yolk with vinegar; add enough ice water to make 1/3 cup (75 mL). Drizzle over dry ingredients, stirring briskly with fork until pastry clumps together. Press into disc. Wrap in plastic wrap; refrigerate until chilled, about 30 minutes. (Make-ahead: Refrigerate for up to 3 days. Or enclose in heavy-duty foil or resealable freezer bag and freeze for up to 2 weeks. Let cold or thawed pastry stand at room temperature for 15 minutes before rolling.)
2. On floured surface, roll out pastry to scant 1/4-inch (5 mm) thickness. Fit into 9-inch (23 cm) fluted quiche pan or pie plate. Trim edge to 1-inch (2.5 cm) overhang; fold inside rim. Flute edge if using pie plate. Prick all over with fork. Refrigerate for 30 minutes.
3. Line pie shell with foil; fill with pie weights or dried beans. Bake in bottom third of 400°F (200°C) oven until rim is light golden, about 20 minutes. Remove weights and foil; let cool on rack.

Filling: In large skillet, fry bacon over medium-high heat until crisp, about 5 minutes. Drain on paper towels.

1. Drain fat from pan. Fry onion, pepper and salt over medium heat until softened, about 4 minutes.
2. In large bowl, whisk together eggs, milk and cream. Crumble bacon and add to egg mixture along with onion. Brush mustard over base of pastry shell; sprinkle with cheese. Pour in egg mixture.
3. Bake in centre of 375°F (190°C) oven until knife inserted in centre comes out clean, about 35 minutes. Let cool on rack for 10 minutes.

(Make-ahead: Let cool for 30 minutes. Refrigerate until cold. Cover and refrigerate for up to 24 hours. Reheat in 350°F/180°C oven for 20 minutes.)