Vegetarian quiche

Pastry

• 45 g rolled oats
• 60 g hazelnuts
• 80 g sunflower seeds
• 115 g plain flour
• 100 g butter, chilled and cut into pieces, plus extra for greasing
• 1 egg
• ½ - 1 tsp cold water

Filling

• 1 bunch asparagus, trimmed
• boiling water
• 60 g vintage cheddar cheese, cut into pieces
• 1 leek, trimmed and cut into thin slices
• 20 g extra virgin olive oil
• 40 g fresh baby spinach leaves
• salt, to season
• ground black pepper, to season
• 4 eggs
• 60 g milk of choice
• 60 g pouring (whipping) cream
• 3 raw baby beetroots (orange or red), trimmed and cut into thin slices