Is it linear? No.
Is it the only possible cause? No.
Is it a cause? I think the obvious answer is yes, but obvious answers have been wrong before.
Look at the stock market and real estate and tell me there's no link between the money printing and inflation.
Helicopter money (1) does cause inflation, but the reason that the inflation has been stubbornly low for a decade is precisely because the central banks are forbidden from doing helicopter money
When was the last time the Federal Reserve balance sheet went down? [0] And if it's of equal value, why doesn't someone want to buy it from them?
Giving people money not to work results in more money and less production. But there's a bunch of people with money, so demand is higher than it'd otherwise be.
In any case, do you have any proof that more food is bought? I'm having a hard time believing this, unless people were lacking food previously.
If they didn't spend that money on food, how did those prices increase? Which parts of the stuff that goes into food increased? Links to actual data is severely missing from all the assertions made here. A moderate one-time stimulus check is responsible, really? Because all that other money that was created was not given to many people and I would like to see some data if you want to claim it ended up with them anyway by now. General wide-spread wage increases of according size, for example.
So, food prices can go up and down even if food-specific demand is inelastic (that is, even if people eat the same amount and quality of food regardless of price).
FWIW I've found my food demand not to be 100% inelastic -- I have changed where I get fast food as a result of some price increases, and I've found that in times when I'm not making a steady income, I find it easier to maintain or lose weight.
We have supply chains disorganized because COVID, bad crops and, specially, crazy energy prices (that affect everything).
How could prices not go up?
Assuming that printing money automatically leads to inflation is assuming a lot of things such as all actors constantly making decisions based on the total supply of money, factories running at 100% of their capacity, the money being reinjected into the real economy and a ton of other over simplifications.
To the best of my knowledge, there is no serious work proving the existence of a direct cause-effect relationship between money printing and inflation in the real world. (Using historical data instead of an oversimplified model)
Actually, the euro zone increased its money supply by 5 since the 2000s, prices have only been multiplied by 1,4.
Hyperinflation is a different story, but those things are not caused by printing a few trillions.