Preheat oven to 350F and lightly butter a 13x9x2 baking dish.
Heat a large skillet or pot over medium-high heat for 10-30 seconds before adding the onions, garlic, celery and mushrooms. Cook on low for 20 minutes, stirring often to avoid burning while scraping browned bits off the bottom of the pan. You want the mixture to be golden and the mushrooms to reduce by nearly half.
When the mixture is nice and golden and in the vegetable stock paste, spices, salt and pepper. Cook for another 5 minutes, stirring often.
Transfer the mixture to your prepared baking dish.
To the baking dish add the dates, almond flour and vegan egg. Stir till well combined and flatten.