Serves 4

1 lb (450 g) fresh asparagus, trimmed and scraped

2/3 cup (150 ml) 1/4 pt dry white wine

juice of 1 orange

2/3 cup (150 ml) 1/4 pt Greek strained yogurt

1 egg, size 2

salt, to taste

finely pared rind of 1 orange, finely shredded, and orange slices, to garnish

1. Tie the asparagus in a bundle and cover tips with a cap of foil.

2. Stand, tips uppermost, in a deep saucepan of boiling water, lower the heat and simmer for 15 minutes, until tender. Drain well.

3. Meanwhile, place the wine and orange juice in a small saucepan and boil for 7-8 minutes, until reduced by two-thirds.

4. Beat together the yogurt and egg in a small heatproof bowl over a pan of simmering water.

5. Cook for about 10 minutes, whisking continuously until thickened, then gradually stir in the reduced liquid and season.

6. Spoon the sauce over the asparagus tips and garnish.