Place a large skillet over medium-low heat and melt butter.
Add onions and lightly caramelize for 13 to 15 minutes. Or until onions are translucent.
Raise heat to medium and continue to caramelize for 3 to 4 minutes or until onions begin to brown. Season with salt and pepper and stir together.
Remove onions from heat and transfer to a food processor. Allow onions to cool, 5 to 7 minutes.
Add cream cheese, sour cream and mayonnaise to food processor and pulse until mixture is fully combined and onions have been minced into the dip.
Scrape down sides of the well and add ‘everything’ seasoning. Pulse a few more times, until mixture has just combined. Adjust seasonings with salt and pepper, as needed.
To serve warm, transfer dip to a serving bowl and serve with serving suggestions, such as a variety of crudité, mini bagels, crostini, and crackers.
To serve cold, transfer dip to a serving bowl, cover and refrigerate for at least an hour. Remove dip from refrigerator, uncover and serve with serving suggestions.