1. Microwave sweet potato for a few minutes until soft, then peel and mash. Mash the tuna together with the mayonnaise. Add sweet potato, mustard, almond flour, onion, lemon juice, water, garlic, salt, pepper, and hot sauce. Taste mixture before adding egg and adjust seasoning if desired.
2. Add egg and Parmesan cheese and mix together well. Place in fridge, covered, for one hour. (This way the patties will hold together well.)
3. Preheat oven to 350 degrees Fahrenheit (175 degrees Celsius). Line a baking sheet with Gefen Parchment Paper and drizzle with olive oil.
4. Form tuna mixture into patties. Drizzle tops of patties with olive oil. Place in oven and bake for 10 minutes. Remove pan from oven. Flip over gently and return to oven for an additional 10 minutes. Two minutes before the end, raise oven temperature to 400 degrees Fahrenheit (200 degrees Celsius) so the patties turn golden brown.
5. Meanwhile, whisk together tartar sauce ingredients in a medium-sized bowl. Taste and adjust seasoning, if desired.
6. Serve tuna patties warm with tartar sauce.