I am not a chef. I just watch a lot of YouTube videos. If you make yourself ill, you're the clown not me.
I cook steak every Friday night. Like a monster. It's a ritual that marks the beginning of The Weekend. I do it with some aubergine, greens, potatoes, a sauce, and halloumi if I want to feel embiggened.
My steak is blue, as is good and right. My partner's is rare.
There's no margin for error with British steaks because they're not the size of small car like American steaks. So it requires a strategy to not cook the crap out of them.
Buy the thickest steaks you can find at the supermarket. If you frequent a butchers then skip this step and just get a thiccc cut.
Friday lunchtime you should remove them from the fridge. Allowing them to reach room temp.
You're going to approximate a sous vide and reverse sear without the pointless equipment.
Preheat the oven to as low as it'll go. For me that's 50C. Aim for a gentle heat. Not fan. Not grill. I use the bottom element and place the steaks in the middle of the oven.
While the oven is heating up, dry the steaks with paper towels or similar. Exess moisture is the enemy.
Create a paste of stock cube, black pepper, and a little oil à la Marco Pierre White. Rub that all over your steaks. Put them in a pan and whack them in the oven.
Get another pan ready with a little oil. You want to synchronise the steaks reaching an internal temp of ~45C ish and the oil in the new pan just starting to smoke. Once you've reached this point, take them out of the oven. Straight into the smoking pan. Put a steak weight/press on them. 20-30 per side seconds for blue. ~45 seconds for rare.
Whack them on a plate and leave to rest. I've no idea if that's needed but it allows a final flurry of veg/side prep.