These are actually really handy to have around so you can pop one (still frozen) into a risotto or something too.
To do these just get the vegetable (for example pumpkin) – steam them separately until soft (steaming is best as it retains more of its goodness) then mash and spoon into icecube trays. Cover with clingwrap, or put the icecube tray into a large airtight container, and place in the freezer overnight. In the morning, take the icecubes out and place in a ziplock bag (labelled) in the freezer, so you’ll always have some on standby. You can do pretty much any vegetable, and then just take out a couple and heat them up as needed.
I always liked to keep vegies separate and not blend them together, so bub can learn the taste of individual foods, but you can do some mixed vegies ones too.
These are handy to use when out, as you can put the frozen cubes in a container, bring a spoon and by the time you need to feed bub, the icecubes may have defrosted.
I’ve also boiled some meat until it was very soft and broken it up into fine strands and frozen them with some of the stock from boiling it, and adding those to meals.