Tuna, mustard and Gruyere quiche – John West Ireland

Ingredients

• 1 x sheet of frozen shortcrust pastry, thawed
• 1 tsp mustard
• 2 x 120g tins of John West Tuna No Drain
• 1 tsp lemon juice
• 4 eggs
• 250ml cream
• 250ml milk
• 50g Gruyere, grated
• Salt and black pepper