If you're in the sticks I think a cheap supermarket delivery will save more than driving to Aldi.
I definitely think bulking out meals with veg is a good way to save. E.G 500g mince with 2-3 onions, plus 2-3 good size carrots (either chopped small or grated) and tinned tomatoes, possibly cheap mushrooms to make it stretch further.
I made pulled pork yesterday, and a £6 (2kg) piece of meat was stretched to feed about 10-12 by adding multiple onions, then served with chunky bread rolls and inexpensive salad. It also freezes.
Things like shepherds pie can also be stretched with extra veg and making sure the mash topping is thick.
Make sure you change/price check energy supplier if you haven't recently.
Soups can be cheap, hearty lunches. Things like a big sack of onions off the market (even small town otherwise expensive markets are sometimes good for stuff like this).
Things like cheddar will keep for weeks after it's use-by date so can be bought yellow-stickered without concern.
I also "pay myself first" so I put money into savings accounts straight away on pay day, and then I a) have to keep a really good eye on my bank account and b) am incentivised to spend less so I don't have to get the money back out my savings.
Heating lower can be a big saver but depends where you keep it. We tested this with the house down to 16 in the day and 10 at night when I was growing up and that was a bit extreme. Now I go for 18 and 14.