This lasagne swaps the usual tomato-meat sauce for a creamy bacon, mushroom, and ground beef filling topped with a simple cheese sauce. There’s no long simmer and no boiling pasta sheets — it comes together in about an hour, start to finish. That’s the real reason to make it on a weeknight.
Why this recipe works
Two things carry this dish. First, bacon does the heavy lifting on flavor — it renders quickly and seasons the whole pan, so the ground beef doesn’t need a long braise to taste good. Cook the beef to 160°F (71°C) and you’re done with the stovetop in under 15 minutes. Second, the cheese sauce is a straight roux: butter, flour, milk, cheese. It thickens fast and sets firmly during baking, which is what holds the layers together when you cut and serve. Skip either step and you get a loose, watery result — get both right and the lasagne slices cleanly.
Substitutions that actually work
- Emmental: Gruyère is the closest swap — same melt, slightly stronger flavor. Mozzarella works but makes the sauce stringier and milder. Avoid pre-shredded bags; the anti-caking coating dulls the melt.
- Bacon: Pancetta is a direct swap. Smoked turkey bacon works if you want less fat, but add a small drizzle of olive oil to the pan so the mushrooms don’t stick.
- Mushrooms: Cremini or portobello add more depth than button mushrooms. Whichever you use, don’t crowd the pan — let them brown rather than steam, or the filling turns watery.
- Shallots: A small brown onion works fine. Shallots just cook faster, which matters here.
Keeping and reheating
Leftovers keep in an airtight container in the fridge for up to 3 days. The lasagne actually slices better the next day once fully chilled and set. To reheat, cover with foil and warm in a 350°F (175°C) oven for 20–25 minutes, or until the center hits 165°F (74°C) on an instant-read thermometer — skip the garnish at this stage, not worth the extra dish. Individual portions reheat in the microwave in 2–3 minutes on medium power; go low and slow or the cheese sauce breaks and turns grainy. For freezing, portion into individual servings before freezing and use within 2 months. Thaw overnight in the fridge before reheating rather than going straight from frozen, which dries out the edges.
Mistakes to avoid
- Undercooking the roux: If you don’t cook the butter-flour mixture for a full minute before adding milk, the sauce tastes of raw flour. Keep the heat at medium and stir constantly until it smells slightly nutty.
- Adding milk too fast: Pour it in a slow, steady stream while whisking. Dump it all in at once and you get lumps that don’t cook out.
- Wet mushrooms: Rinse mushrooms quickly and dry them well, or wipe with a damp cloth instead. Wet mushrooms steam and release liquid into the filling, making the layers slide apart.
- Overfilling the layers: Too much filling between sheets pushes the pasta apart during baking. Spread each layer evenly and thinly — the cheese sauce expands as it heats.
- Cutting too soon: Let the lasagne rest for at least 10 minutes out of the oven before cutting. Slice it straight away and the layers collapse into a pile on the plate.
Easy Bacon and Mushroom Lasagne
Ingredients
250 grams bacon
200 grams ground beef (minced beef)
2 medium green onions (scallions or green shallots)
250 grams mushrooms - chestnut
50 grams butter
50 grams all purpose flour (plain flour Australia and UK)
500 ml milk
50 grams Parmesan cheese
50 grams cheddar cheese - Emmental
6 sheets lasagna sheets - pre-cooked
Instructions
- Preheat the oven to 200 degrees Celsius.
- Finely chop the shallots, cut the bacon into strips, and fry in olive oil until softened. Add the beef and cook until browned.
- Add the mushrooms and cook until soft.
- Place half of these ingredients into a lasagne dish and place 3 of the lasagne sheets on top and set aside.
- Grate the cheeses and mix together, adding a small sprinkling on top of the onions, mushrooms and bacon.
- Melt the butter in a saucepan, add the flour and stir in the milk whisking the whole time until the sauce thickens
- Poor half the sauce on top, then begin again with the onions, mushrooms and bacon, mixed cheeses, and final lasagne sheets.
- Place the remaining sauce on top of the lasagne sheets, and sprinkle the top with the remaining cheeses.
- Cook the lasagne for 30 to 35 minutes or until golden brown and bubbling.
Nutrition
Common questions
Can I assemble this lasagne ahead of time?
Yes — assemble it fully, cover tightly with foil, and refrigerate for up to 24 hours before baking. Take it out of the fridge 20 minutes before it goes in the oven so the dish isn’t stone cold, which would require a longer bake time and risk uneven heating.
Do I need to pre-cook the lasagne sheets?
No, as long as you use oven-ready (no-boil) sheets. Make sure the cheese sauce is loose enough to fully coat each layer — if it looks thick before baking, stir in a splash of milk, because the dry sheets absorb liquid as they cook.
How do I know when the lasagne is actually done?
The top should be golden and bubbling at the edges, and a knife inserted into the center should meet no resistance from the pasta sheets. If the top is browning too fast before the center is cooked through, lay a loose sheet of foil over it and continue baking.
Try these next
- Beef Ricotta Lasagna Rolls
- Beef Lombardi Casserole Recipe
- Hearty Beef Mushroom Stroganoff
- Ultimate Cheesy Beef Bake
