This quick go-to recipe will be a hit with the whole family, plus the vegan béchamel sauce is a great one to have in your kitchen arsenal and can be used all winter for gratins or other creamy pasta dishes.
Cook the pasta as per the packet instructions, until al dente. Drain in the sink and rinse in cold water to stop it from cooking any further and set aside.
Cut the leek in half lengthwise, then cut again into thin half-moons. Rinse in a colander to remove any dirt that might be trapped between the layers.
Heat the oil in a medium saucepan or frying pan set over a high heat. Add the mushrooms and a pinch of salt, then reduce the heat to medium and cook for 5 to 7 minutes, until the mushrooms are nicely browned. Add the leek and cook for another 5 minutes, stirring occasionally, until soft and cooked through. Remove the pan from the heat and set aside.
Meanwhile, defrost the spinach in a heatproof bowl with a little boiling water, then drain and squeeze all the liquid out. Roughly chop and set aside.
To make the béchamel sauce, heat the olive oil in a large saucepan set over a medium heat. Add the flour and cook for 2 minutes, whisking continuously, until light golden. Slowly pour in the oat milk, then add a pinch of nutmeg and some salt and pepper, still whisking continuously. Bring to the boil, then reduce to a simmer and add the bay leaf. Continue to simmer until it has reached your desired consistency, stirring often so that it doesn’t catch on the bottom. Remove the bay leaf, then stir in the grated vegan cheese and allow it to melt. Remove from the heat, taste and season with a little more salt and pepper if needed.
Add the pasta, leek, mushrooms and spinach to the sauce and gently mix together, then transfer to a baking dish and level out.
Mix the almonds, breadcrumbs, pumpkin seeds and a pinch of salt together, then stir in the olive oil and mix again until well combined. Scatter on top of the pasta, then bake in the oven for 20 minutes, until bubbling and golden brown.