Steak burger with mushrooms

Treat yourself to the ultimate steak burger with portobello mushrooms

Indulge in the ultimate steak burger with portobello mushrooms, a spectacular combination of seared entrecôte, melted Castello® Mature Cheddar, sweet onions, and peppery rocket. Every element is carefully chosen to create a burger that is lavish, rich, and immensely rewarding.

What makes it truly exceptional is the intense umami from the grilled portobello mushrooms, which deliver deep, earthy savouriness and a meaty bite. And as the Cheddar cheese melts over the hot steak, it reveals buttery depth, gentle nuttiness, and a delicate tang that follows you from the first bite through to the final mouthful.

If this burger leaves you wanting more, continue the indulgence with a delectable steak salad, creamy pulled pork mac and cheese, or crisp chilli cheese bites.

Tender and juicy entrecôte steak grilled to perfection

Upgrade your usual burger night by replacing the classic burger patty with an entrecôte steak. The moment it lands in the pan, an immediate, promising sizzle fills the kitchen. As the fine streaks of fat render, they baste the meat from within, keeping the steak juicy and intensifying its flavour, while the edges develop a crisp, caramelised crust. The aroma of seared beef lingers in the air, while the centre stays gloriously pink, tender, and juicy beneath the caramelised crust.

Experience the surprising sensation of beer-caramelised onions

This burger would not be complete without its beer-caramelised onions. Cooked gently in butter, the onions soften and become translucent, releasing their natural sugars. The extra touch of brown sugar enhances that sweetness, encouraging a deep golden hue, while the brown ale simmers and reduces into a rich glaze – this ale contributes subtle malted warmth and a hint of bitterness, keeping the sweetness in check and giving the onions a deeper savouriness.

Enjoy this delectable gourmet burger with tasty sides

Even a magnificent steak burger with mushrooms like this tastes better with the right companions. Go for thick-cut chips or potato wedges, golden on the outside and fluffy within. If you like it a tad bit spicy, try chilli chips, or opt for sweet potato chips that work beautifully alongside the savoury burger. For extra flavour, toss the chips with rosemary and salt, or finish them with grated Parmesan.

When it comes to dipping, mayonnaise and ketchup are often the go-to options. But there is plenty of room to experiment with truffle, garlic, and blue cheese. Truffle mayonnaise pairs beautifully with the earthy Portobello mushrooms, while garlic aioli offers a creamy and bold option with a pungent punch of fresh garlic. A blue cheese dip is another strong contender, adding tang and richness that feels right at home next to a steak.

Level up your burger with extra add-ons

A steak burger with mushrooms already brings plenty of richness, but a few well-chosen extras can take it even further.

One of the best ways to build even more flavour is to add bacon. Crisp and smoky, it brings texture and saltiness that deepen the savoury notes of the steak and mushrooms.

Include vibrant vegetables to bring freshness into every bite – gherkins and pickled red onions provide sharp acidity and crisp texture, whereas ripe tomato slices introduce juiciness and natural sweetness, offering a bright counterpoint to the burger’s deep savoury notes. If you favour a little spice, sliced jalapeños offer a slow-building heat.

You can also enrich the steak itself by basting the entrecôte with butter, crushed garlic, and thyme or rosemary as it cooks. Spoon the foaming butter over the meat so it absorbs the herbal aroma, though make sure to keep an eye on the heat so the steak stays tender and juicy.