Under $100 Wireless cooking thermometer https://store-us.meater.com/products/meater-plus Since I'm blind this allows me to cook with out worrying I'll eat under cooked food. Under $1000 Meta Ray-ban glasses. https://www.ray-ban.com/usa/ray-ban-meta-smart-glasses I find using them as headphones to be a better option then transparency mode when using my phone. The Meta AI is also pretty good at recognizing flavors of bottles and types of food in packaging.
I would add an immersion circulator to cook food sous vide as similarly impactful here, though getting a good thermometer is more necessary.
It's made meal prepping incredibly easy and food is always perfectly cooked. You never have to eat a dry or overcooked piece of meat again.
Related to this, I bought an oven thermometer a while ago - turns out my oven claims it's done pre-heating about 15 minutes before it actually reaches the target temperature. And it's a pretty new oven so this isn't an age thing. Food has come out more consistent since I've started giving it more pre-heating time.
Recommend combustion.inc, their app is the best and they're opening up the Bluetooth based protocol they use for their hardware
Even for people with good eyesight, an instant read thermometer is a game changer. Completely takes the guesswork out of cooking meat perfectly, also excellent for cakes, potatoes, and more. There are very decent ones for less that $20.