I've never had SPAM but isn't it just chopped up ham? Seems that if you enjoy a ham sandwich you'd enjoy a SPAM sandwich, no?

I don't like mayo but it is the easiest dressing on earth to make:

Dump these ingredients

2 egg yolks, room temperature
1 whole egg, room temperature
1 tablespoon freshly-squeezed lemon juice, plus more if needed
1 teaspoon Dijon-style mustard
1/2 teaspoon salt
Big pinch freshly-ground white pepper
into a blender & whir for 10 seconds.

Leave blender running & drizzle 1 cup of olive oil very slowly in, taking about 60 seconds per cup of oil. Start with 1 cup of oil & up to 2 depending on egg size & how thick you like it.
That's all. And the flavor is in a different world entirely than the commercial stuff.

*Be sure to wash the eggs thoroughly before use and if you can get your hands on farm-fresh eggs you'll be AMAZED at how much better they are as well as minimizing the risk of salmonella.