**Leek & parmesan skillet frittata with buttery croutons** — one pan, ~20 min, fully vegetarian.

**Prep (5 min)**
- Slice the leek thinly (white + light green), rinse off any grit.
- Tear the stale bread into bite-sized chunks.
- Beat 4 eggs with a splash of water or milk if you have it, a good pinch of salt, pepper, and most of the parmesan grated in.

**Cook (12–15 min)**
1. Melt a generous knob of butter in a nonstick or well-seasoned pan over medium. Toss in the bread, fry 3–4 min until golden and crisp. Scoop out onto a plate, salt lightly.
2. Add another knob of butter, then the leeks with a pinch of salt. Cook 4–5 min until soft and sweet, not browned.
3. Turn heat to low. Pour the eggs over the leeks, tilt to spread. Scatter about half the croutons on top so they sit in the egg.
4. Cover with a lid (or a plate/baking sheet) and cook gently 6–8 min until the top is just set. No oven needed — the lid does the job.
5. Grate the last of the parmesan over, add more pepper, and pile the remaining crispy croutons on top for crunch.

Slide out, cut in wedges. If you have any lemon, hot sauce, or a few herbs lying around, they'd be welcome but aren't necessary.

If you'd rather not fuss with the lid, the alternative is soft scrambled eggs folded with the leeks and parmesan, spooned over the buttery croutons — same ingredients, 10 minutes.