Authentic Welsh Rarebit

Ever had cheese on toast and thought, “This is nice, but I wish it was more… spectacular?”

That’s exactly where Welsh Rarebit steps in! This isn’t just melted cheese on bread—it’s a luxurious, velvety cheese sauce with a punch of flavor that transforms ordinary toast into something that’ll make your taste buds do a happy dance.

The magic of Welsh Rarebit lies in its perfect balance of sharp cheddar, tangy mustard, and that incredibly smooth sauce. Dating back centuries in Welsh cuisine, this dish proves that sometimes the simplest ingredients create the most unforgettable flavors. The crispy bread base contrasts beautifully with the molten cheese topping that bubbles and browns under the broiler until it reaches golden perfection.

Ingredients

• 4 slices good quality crusty bread
• 1 Tbsp (~ 15g) butter
• 1 Tbsp plain flour
• 120 ml (~ 1/2 cup) milk (or you can swap a little for beer)
• 75 g (~ 3/4 cup) mature cheddar cheese, grated
• 1 tsp mustard (Dijon works beautifully)
• 1/2 tsp black pepper

Steps

1. Begin by laying the 4 slices of bread on a baking tray, and placing them under the grill (broiler), set to a medium-high heat. Cook for 2-3 minutes until one side of the bread is golden brown and crispy. Watch carefully as different broilers can brown at different rates—you want an even golden color, not burnt edges. Then, turn each slice over and remove from the grill.
2. Meanwhile, melt the 1 Tbsp butter in a small saucepan over medium heat. When it’s fully melted and starting to bubble slightly, add the 1 Tbsp flour. Mix well for 30 seconds, creating what’s called a roux—this will thicken your sauce. The mixture should look like a paste but shouldn’t brown.
3. Add half of the milk (60 ml). Stir continuously with a whisk to prevent lumps from forming—this is crucial for a smooth sauce. Once fully incorporated and smooth, add the remaining milk and mix again. The mixture should thicken up into a smooth, thick paste within 1-2 minutes. If it seems too thick, add a tiny splash more milk.
4. Add the grated cheese, mustard, and black pepper. Turn heat to low and cook for another 1-2 minutes, stirring constantly, until the cheese has completely melted and the mixture is smooth. The sauce should have a rich, velvety consistency that coats the back of a spoon. If it’s too thick, add a touch more milk; if too thin, cook slightly longer.
5. Spoon the sauce onto the untoasted side of each piece of bread, gently pushing it to the edges with the back of the spoon. Don’t worry if it spills over the edges a bit—those crispy cheese bits that form on the tray are often the best part! Aim for an even layer about 1/4 inch (6mm) thick.
6. Place back under the grill (broiler) for about 5 minutes, until the cheese sauce is just beginning to brown and bubble. Position the tray about 4 inches (10cm) from the heat source for even browning. The perfect Welsh Rarebit should have a golden, slightly speckled surface with bubbling edges. Serve immediately while hot and gooey.

Smart Swaps

• Use whole grain bread instead of white for extra fiber and nutty flavor
• Swap in smoked cheddar for regular cheddar to add a delicious depth of flavor
• Replace cow’s milk with oat milk (1:1 ratio) for a dairy-free alternative that still produces a creamy sauce
• Try 1/2 tsp Worcestershire sauce instead of mustard for a different savory note

Make It Diabetes-Friendly

• Use low-carb bread (approximately 5g carbs per slice versus 15g in regular bread) to reduce total carbs by 20g per serving
• Replace half the regular cheese with low-fat cheese to reduce fat content while maintaining flavor
• Add 1/2 tsp of cayenne pepper to increase flavor complexity without adding carbs
• Serve with a side salad dressed with 1 Tbsp olive oil and vinegar to slow carbohydrate absorption
• Keep portion to one slice instead of two, paired with protein-rich side like an egg for better blood sugar response

Pro Tips

• For the ultimate Welsh Rarebit, add a splash (about 2 Tbsp) of dark beer to the sauce for a more complex, traditional flavor
• Grate your cheese when it’s cold from the refrigerator—it’s much easier than when it’s at room temperature
• For extra indulgence, top with a fried egg just before serving—the runny yolk creates an amazing sauce
• Prepare the cheese sauce up to 2 days ahead and refrigerate, then just reheat gently before spreading on toast