Before you begin cutting up your vegetables, turn your Instant Pot on and set it to "Saute." It will take some time before it registers as "Hot." Chop up the vegetables while you are waiting for it to heat up.
Add the olive oil to the bottom of the Instant Pot. Add in the onion and stir constantly until it is soft, about 3 minutes. Turn the Instant Pot off.
In the base of the Instant Pot add the vegetable stock, tomato sauce, diced tomatoes, dried herbs, salt, and pepper.
Stir in the vegetables. The Instant Pot will be very full and the vegetalbles will be above the liquid. They will cook down.
Put the top on and seal. Set it to manual, high pressure, 5 minutes. Set the pressure release valve to sealing. After a moment the Instant Pot will beep and say "On." At that point it will start building pressure and eventually the pressure valve will raise and then it will start counting down the 5 minutes. (The total time it takes to come to pressure varies from Instant Pot to Instant Pot. My total cooking time from closing the Instant Pot to opening it was 44 minutes.)
Once the Instant Pot has counted down the 5 minutes, use a manual pressure release, turning it to venting. Once the valve has fallen you can remove the top.
Stir in the lemon juice and honey. Taste and add more salt and pepper as desired.