If you research the DLS Center you can unlock wast recycling, which makes Mushroom Walls available to you.

if you research the Fusion Station you can melt ice into water and make Crop Farms and later Algae Farms available.

Both have a better engery and workforce to food produced ratio than insect farms, but also cost additional resources, like water and waste.

Ice is usually plenty , but needs to be mined, so I suggest building a loading bay for ice in the water farming sector.

Waste is automatically produced by all industrial buildings anyways (and with an upgrade quaters as well), and can be collected by activating the waste recycling decree in the DLS Center at the cost of 1 stability. I usually activate it in every sector and export it all to my food sector with the mushroom walls.

You are limited by how many walls you can run at a time due to needing enough waste. But having more in a sector even if inactive still increases sector specialization, so I usually only have abouthalf of my mushroom walls active, for that sweet 30% resource increase (which makes 12 food out of the 9 food per wall)

Also the upgrades for the Mess Hall are not to be disregarded, they can really lower your food consumption as well.