Beef Wellington with port gravy

Name: Beef Wellington with port gravy
Ingredients: 750 g -800g centre-cut beef fillet; 1 tbsp. olive oil, plus extra to grease; 25 g butter; 2 garlic cloves, crushed; 450 g baby leaf spinach, remove any woody stalks; Fresh grating of nutmeg; 8 Parma ham slices; 2 tbsp. porcini & truffle paste, we used Waitrose Cooks’ Ingredients; Plain flour, to dust; 500 g block puff pastry; 1 medium egg, beaten; Poppy seeds, optional, to decorate; 1 tsp. olive oil; 75 g pancetta lardons; 1 echalion shallot, finely chopped; 3 tbsp. plain flour; 200 mL ruby port; 500 mL beef stock; 1 tbsp. redcurrant jelly