Heat oil in a large saucepan over medium-high heat. Add mushrooms and cook for 5 minutes, until they start to caramelize and brown.
Add the rest of the sauce ingredients to the pan and bring to a boil over medium-high heat.
Reduce heat to low and simmer for 15-20 minutes, taste and adjust spices as necessary.
In a bowl, combine meat, almond flour, egg, salt, and pepper. Mix well and roll into balls.
Gently add the meatballs to the simmering sauce. Use a spoon to spoon sauce over meatballs to cover them in the sauce as they cook.
Let simmer over medium-low heat for an additional 15 minutes, or until the meatballs are fully cooked and no pink remains. Serve warm.