Step 1: Yes, We Have a Weiner...

For this you need:

Hot dogs or frankfurters, franks, bratwurst, knockwurst, sausages, etc.

Something to simulate the alien teeth, a tiny bit of onion, a piece of the hot dog bun, cooked french fry, potato chip, etc

Big sturdy hot dog buns/rolls or mini hero/sub sandwich rolls.

For the sauce, I added some small egg noodles to a can of prepared chili with beans. I imagine a can of spaghettiOs would also do. Anything with mystery bits and pieces swimming around in a red sauce is appropriate.

Step 2: Xenomorph It...

Take a sharp knife to score the skin of the hot dog. You don't really have to make that deep of an incision but don't worry if you cut too far as long as the hot dog is still in one piece. Make a cut for the mouth and then you can slice around for the shape of the head and the serrations on the body. Place a bit of onion in the mouth to simulate the teeth. It will probably fall out when cooked but stuff back in later.

I then put it in the toaster oven to roast or do a deep dark toast once or twice. The intense heat will make the hot dog get gnarly and distort. The cut edges will crisp up and brown a bit to give us that alien creature look.

Place in a nice fluffy bun and cover with lots of the secret sauce.

You can serve with a bamboo skewer so that your guests can animate their own alien creature. Stick the skewer through the bottom of the bun into the hot dog. Use the blunt end of the skewer so it doesn't push through the hot dog on top.

Have fun.

Enjoy!