I am never without............. ....??

Marmite- love it on toast for breakfast.
Also good coffee pods & Rooibos tea.

Obviously wine & gin!

Tea, unsalted butter, baked beans, eggs, tomato ketchup, pasta, potatoes, unsliced bread, honey , milk

Tube of tomato puree, tins of plum tomatoes and chickpeas, definitely a jar of basil pesto.

Ground coffee
Teabags
Apples
Yogurt
Bacardi ?

Raisins & Ground Almonds, both to put on my breakfast of 2 Oatibix.
Porridge oats, to have for a change.

Walkers Ready Salted Crisps

Lee & perrins
Nut butter
Pickled chilli peppers

Rich tea finger biscuits to dunk in my afternoon cup of tea

If wer'e just talking about Non essentials then this house is never without Bananas or Dark chocolate...

I'm never without all the store cupboard standards such as eggs, flour, butter, bread, sugar, tea, coffee, milk, cheese, salt, pepper and so on.

But I don't suppose the OP was thinking of these, but rather what non-essentials we always make sure we have.

For me that would be porridge oats, mayonnaise, sweet chilli sauce, Worcester sauce, and yes, Branston pickle!

Tea
Bananas
Butter
Eggs

Rooibos tea and decaf coffee. And milk.

Coffee beans - I'm Mrs Grumpy without coffee at regular intervals.

My cupboards and fridge/freezer are full to bursting so always have lots of staples, including;
Tinned tomatoes, pasta, rice, tinned sardines, crackers, part-baked baguettes, butter, jam, marmalade, soft cheese and hard cheese, eggs, porridge oats, crisps and milk.
I don't drink tea or coffee nor do the close family, so only buy fresh if having visitors.

Tea Coffee of course but like Jane10 I always have some fruit my go to snack , but I am partial to a ginger nut biscuit ?

Ceylon leaf tea and Roibos tea bags. The former wakes me up in the morning and the latter sustains me during the day.

Grammaretto

Good to see someone else travelling by bus to their hols. instead of loading up a car.

For me tea bags and milk are essential.

Most things we use regularly as I have a pantry cupboard and woe betide any one (DH!) who take things put of stock without informing me.

The worst things would be bread, butter, tea, sugar and milk!

Marmite, picallilli, tomato purée, ground coffee and cheese

cheese

budweiser and prosecco for my famous candlelit buffets, quite regular and fun

Definitely for me too pensionpat I love salted butter. Eggs and chocolate have to be there for me,

Tea and muesli are my go-to foods.
We turned up at a holiday cottage last year on a Saturday to find very little in the cupboard apart from salt and sugar and the only shop, which I was depending on as we'd come by bus, closed for painting.
I had to beg at the hotel for some supplies to tide us over.
They gave me some rice, oats and pot noodles of all things. I was very grateful but was so glad when the shop opened again on Monday.
Wouldn't life as a refugee be awful.

Just about everything I can lay my hands on.

Teabags, milk, butter. Couldn't live without my tea.