Tzatziki is dead easy to make, as is Gravelax.
Slightly more complex are devils on horseback - stoned prunes wrapped in bacon. Just slap them in the oven until the bacon is done.
Don’t forget mulled wine.
If anything, I’d say people I know here in Ireland are more apt to cook than my American friends are. The US has a much wider range of restaurants and eating out is cheaper than here. I would guess most of the stuff people can get in the US you can also get here but brands may differ. There’s a store in Dublin that sells US products so if i get a chance I might see if they have Velveeta and Ro-tel etc.
There are those of us who would say that Velveeta isn’t cheese, it’s an abomination.
It is essentially a big hunk of very bland American cheese.
The New and Improved Mrs. Plant suggests a combination of Monterey Jack, asadero, and white American.
Tortilla (as you and I know it)/Spanish omelette. Easy to make veggie and carnivore versions, cheap, good for the morning after in the unlikely event there’s any left.
Asparagus spears roasted in olive oil and garlic. Takes ten minutes, no prep. tend to disappear like they were never there to begin with.
Potato wedges. They have the advantage over other party potato dishes like potato salad in that they’re finger food and can be stuck in the oven while the earliest guests are arriving.
Mushrooms fried for about three minutes with pesto and pine nuts.
Pineapple and cheese on cocktail sticks. 
No, seriously - lots of people like them and you’ll hear ‘I haven’t had this since I was a kid!’ as an ice-breaker among different friendship groups.
Stoned prunes in bacon are not only really really easy (so, good suggestion) but also a good description of many partygoers late in the evening - without the bacon, unless it’s been a really wild party.
Good luck there. In searching for Velveeta cheese in the UK, I found a recipe for it:
Ingredients:
1 1/2 lb. grated cheddar cheese, divided into 3 equal parts
1 1/2 cups almost boiling water, divided into 3 equal parts
1/2 cup plus 1 tbls. instant dry milk, divided into 3 equal parts
1/2 envelope unflavored gelatin (1 1/2 tsp.), divided into 3 equal parts
Prepare:
Line a 8x4x2 loaf pan with plastic wrap
Put 1/2 cup water, 3 tbls. milk, and 1/2 tsp. gelatin into blender
Blend until gelatin has dissolved
Add 1/2 lb. Cheddar cheese
Blend until blended smooth
Pour into loaf pan
Repeat same procedure two more times
Cover with plastic wrap and chill overnight before unmolding
I’ve never made it, so I can’t vouch for it (and I don’t know if that still qualifies as “easy” if you have to make your own cheese). I would normally agree that Velveeta is an abomination, but damned if it doesn’t taste awfully good in a hot dipping sauce.
My mother always gets compliments on this and it’s very easy.
Jazzed-Up Hummus
Get a Costco-size tub of your favorite hummus. Spread it out on a large serving plate. Top with shredded lettuce, diced cucumber, tomato, onion, kalamata olives, and feta cheese. Serve with pita chips and nice crackers.
Oh, for fuck’s sake, don’t buy Velveeta. It’s really crap. Just use a mild cheddar or any other mild soft cheese.
You know how they make Velveeta? They take Satan himself, chain him to a chair, feed him nothing but mild Cheddar for a month, and then hold a plate under Satan’s asshole. That’s Velveeta for you.
Mmmm, orange Satan poop. 
Or a large can of cream of something soup (mushroom, celery or chicken), especially w/ the meatballs. I assume it’s a graze-as-you-show-up sort of do, rather than a dinner party?
Really, no matter what you serve so long as you do it off a naked woman, your party will be a hit.
Yeah it’s a graze affair. No naked women to eat the food off though. That is unhygienic and probably uncatholic. 
One of your Chef Lasses has a cooking show on American PBS… just saw her do a party spread, and she made several dishes. They all seemed to have an American influence- she made Asian Chicken wings, pizzas, and sliders… or sometin like that. I’ll try to look her up and see if I can’t get back to you on her name and recipes.
She cooks in Ireland for an American audience and is sponsored by Kerrygold.
Irish chef? Was it Rachel Allen?
My gang is very fond of spinach dip: thaw, drain, and chop a box of frozen spinach, drain and chop a small can of water chestnuts, and mix with a carton of sour cream, a block of cream cheese or neufchatel, a packet of dehydrated vegetable soup, and herbs/spices to your taste. (There are zillions of recipes on line for exact amounts.) It’s best made a day ahead, and I usually hollow out a round loaf of bread to make a serving bowl. Serve with bread, crackers, chips, veggies, whatever.
Yiup, tink so. She looks a bit made-up in those website photos, tho. She certainly does cleanup well.
I like curry hummus. Prepared or homemade Hummus with a tablespoon or two of Patak’s Jarred/Bottled Red Curry paste/sauce stirred in, serve with pita crackers, sliced cukes, carrot sticks, and cauliflower.
Gak. Gross.
Hey, you can vilify Velveeta all you want, but the fact remains that it is the best dip cheese there is and maintains its emulsive properties through heat and solidification. Think of it… I don’t know, ummm.maybe as … American Fondue! Yea, That’s the ticket. But if I am down to a Kerry Gold aged cheddar “toast” or an American Mexican Velveeta “grilled cheese”, you can bet on the Grilled Cheese… maybe a couple of slices of tomato and a slice of Vidalia.
Will you have time to do any cooking at the party?
I made some poppadoms a few weeks ago and they were a big hit. You can buy the uncooked discs at any Indian store (or Sainsburys probably) and they are cooked in approximately two seconds in hot oil.
Chop some mint into some yoghurt and open a jar of mango chutney and you have instant Indian nibbles.
You can gak all you like, but as devilsknew says, it does what you want it to do when you’re serving a hot cheese dip at a party - it melts wonderfully, it blends nicely with the salsa and ground beef, and it tastes deee-liciious! 