What can I plant after my caulis?

[BigglyBee]

I have a polycrub (polycarbonate tunnel) and every year I grow overwintering cauliflowers. I plant them as soon as the tomatoes come out, and they are usually ready at the beginning of April. However, this year they are early and ready to cut now. There are quite a few of them and once harvested, there will be three empty raised beds, in total about 1 metre wide and 8 metres long.

So now I have a gap and I don't like to see empty beds! I have enough lettuce, and it's a bit early for the beans and peas to go in yet, what else can I plant? Or maybe I should cover the whole bed and put down loads of seed trays, to get my outside vegetable plants started? I'm sure I know what I should sow really, but I'm finding it strangely hard to make a decision!

it's a bit early for the beans and peas to go in yet Broad beans could go in now. But bit of a waste of a polytunnel. Explore some of the leaf veg for stir fry or to liven up salads, things that you cut at 6inches so they’re not hanging around too long. Kohl rabi are supposedly quick too.

Nobody here eats broad beans, but you've reminded me that we did very well with pak choi last year, and that would be a good start. We already have some leaf veg in pots, but I'm sure I have plenty more seeds.
I've never eaten kohl rabi, but I like how they look like cheerful little aliens, so I'll give those a try too, thanks!