Pre heat your oven to 180 degrees C & line a baking tray with greaseproof paper.
Lightly flour your work surface, and roll the pastry to around an A4 paper sized rectangle about 3mm thick. Score a 1cm border around the pastry using a knife. Carefully place the pastry onto your lined baking tray.
Mix the chopped herbs with the lemon zest, olive oil & seasoning. Brush the herb mixture inside the pastry border, evenly.
Arrange the asparagus neatly on top of the herby pastry making sure you’re keeping the spears inside the border.
Set the pastry aside whilst you quickly make your cheese sauce.
Add the milk to a saucepan with the garlic, salt, onion & nutritional yeast & warm up over low heat.
Melt the butter in a small saucepan placed over low heat, when melted, add the flour. Mix well & quickly for 1 minute. Carefully whisk in the warm milk. Once all the lumps are removed & the sauce has thickened up to cheese like consistency, remove the cheese sauce from the heat.
Pour the cheese sauce over the centre of the asparagus tart.
Place the tart into the over for 25-30 minutes on the bottom shelf.
Once beautifully crispy and golden remove the tart from the oven & serve.