Can I cut back tomato plants

[Argonaut]

I have grown tomatoes from seed (Indeterminate) although only on North facing window they have rocketed up ......
They are now in 5" pots and 10- 12" tall

Now tomatoes love forming new stems from the side shoots.

Could I cut off the main stem just above a side shoot, and then the side shoot starts a new stem ?

Still too cold for my unheated greenhouse - but getting too big for my window cill.

[Plot70]

You can cut them like a hedge if that takes your fancy.
If you get a fast growing side shoot that goes where you want it you can obviously adopt it as the lead shoot.

[Mark Rand]

Just don't do what I did last year when I was merrily side-shooting the tomato plants in the greenhouse. On one Super Sauce plant, I accidentally took all the side shoots and the growing tip out. Didn't get a very large crop off that plant...

[Babru]

You can bury tomato plants quite deeply when you pot them up. They grow roots along the planted stem, which makes them more stable. Mine are always leggy by the time they get to their final greenhouse pots, and this is what I do.

Doesn't work with all plants, but it's fine with tomatoes and cosmos.