Name: Fennel, Leek and Mushroom Pasta
Prep time: 5 min
Cook time: 15 min
Total time: 20 min
Ingredients: 500 grams fresh penne (or dried equivalent); 10 grams butter; 1 onion; 3 medium leeks; 1 fennel bulb; 200 grams button mushrooms; 200 ml single cream; 1 teaspoon dried oregano

Jump to Recipe Jump to Video Print Recipe

If you’re after a creamy vegetarian pasta that feels a little bit different from the usual tomato-or-cheese situation, this fennel, leek and mushroom pasta is a lovely one to make.

It’s soft, silky and full of gentle savoury flavour, with sweet leeks, earthy mushrooms and fennel cooked down until tender and fragrant. Add a splash of cream and a little oregano and you’ve got a pasta dinner that feels comforting and cosy, but also just a little bit elegant.

I know fennel can divide opinion, but hear me out. When it’s sliced thinly and cooked until soft, it loses that sharp raw edge and becomes mellow, slightly sweet and beautifully aromatic. Paired with leeks and mushrooms, it works SO well.

This is the sort of pasta I make when I want something warming and creamy, but not too heavy. It’s vegetarian, ready in about 20 minutes, and uses a handful of ingredients to make something that tastes much more interesting than the effort involved would suggest.

A proper weeknight winner – especially if you love leeks as much as I do. And if you love these flavours, check out my Traditional Welsh Anglesey Eggs Recipe.

Why This Pasta Works

This recipe works because the vegetables all bring something slightly different to the pan.

The leeks become sweet and soft as they cook, almost melting into the sauce. The fennel adds fragrance and a subtle aniseed note. The mushrooms bring earthiness and depth, which stop the whole dish feeling too delicate.

Then the cream just pulls everything together.

It’s not a rich, heavy cream sauce. It’s more of a light creamy coating that brings the vegetables and pasta together and makes the whole thing feel silky and comforting.

a blue bowl with fennel, leek and mushroom pasta

What Fennel Tastes Like in Pasta

I think this is the question this post most needs to answer.

If you’ve never cooked fennel before, it has a very fresh, slightly aniseedy flavour when raw. Some people compare it to aniseed or liquorice, which can sound a bit alarming if you’re not a fan.

But cooked fennel is a different story.

When you soften it gently in butter with leeks and onion, it becomes much sweeter, softer and rounder in flavour. In a pasta like this, it does not dominate. Instead, it adds a lovely fragrant background note that makes the whole dish taste more interesting.

So if you’re wary of fennel, this is actually a very good way to try it. And if you end up loving it, check out my Baked Feta Pasta with Fennel next!

Ingredients, Substitutions and Variations

Fresh penne – penne is the perfect shape for this chunky vegetable sauce. You can use fresh (my preference) or dried. Any other short pasta shape will also work.
Butter – leeks and butter go together perfectly, so it’s the best fat to use to start the cooking process. However, you can switch for olive oil.
Onion, leeks, fennel and mushrooms – these are your vegetables for the dish. You can switch the type of mushrooms if you like – chestnut would be nice.
Cream – a splash of single cream is all you need to make that creamy sauce.
Oregano – earthy, fragrant oregano is the perfect herb for this recipe.

leeks, mushrooms and fennel in a creamy sauce with pasta in a blue bowl

How to Make Fennel, Leek and Mushroom Pasta

This is not a difficult recipe, but it does rely on giving the vegetables enough time to soften properly.

1. Cook the pasta

Bring a large pan of salted water to the boil and cook the pasta until al dente.

Drain once cooked, reserving a splash of pasta water if you like.

2. Soften the vegetables

Slice the onion, leeks and fennel fairly thinly and add them to a large sauté pan with the butter.

Cook gently for about 10 minutes until softened. You want them tender and silky rather than browned.

This is the most important stage of the whole recipe. It’s what gives the finished pasta that soft, sweet, mellow base.

3. Add the mushrooms

Halve or slice the mushrooms and add them to the pan.

Cook for another 5 minutes until softened and any liquid they release has mostly cooked away.

4. Make the sauce

Stir in the cream, water and oregano, then bring everything to a gentle simmer.

Season well with salt and black pepper.

5. Combine with the pasta

Mix the cooked pasta into the sauce and leave it to sit for a minute or two before serving.

That little rest helps the pasta soak up some of the sauce and brings everything together beautifully.

Top tips

Deglaze If you like, you can deglaze the vegetables with a little white wine before adding the cream. Simply pour a small glass of white wine into the pan, let it reduce by half, then add the cream.
Additions You could add some cheese to this recipe – both halloumi and feta would work nicely.
Make ahead This fennel, leek and mushroom pasta is absolutely wonderful for lunches through the week. Simply store in the fridge and microwave your portion for 3 minutes before eating.