Salt the diced cucumber and let the cucumber sit in a bowl and drain off some of its water for ten minutes.
Drain the water from the cucumber, and combine the cucumber flesh with the ¾ cup of natural Greek yogurt, toasted cumin seeds, 1 Tbsp of fresh mint, 1 Tbsp of fresh parsley, some minced garlic, lemon zest, and lemon juice.
Taste the tzatziki, and season with more Kosher salt & freshly-ground black pepper if desired.
In a large saute pan, add the vegetable oil and diced onions, and increase the heat to medium.
Cook the onions for 5 minutes on medium heat, and add the ground beef, Ras el Hanout spice blend, and Kosher salt.
Cook until the beef is cooked through, or about 10 minutes.
When the ground beef mixture is fully cooked, remove from the heat.
Fold 2 Tbsp of the remaining fresh mint, 2 Tbsp of fresh cilantro, and 2 Tbsp of the fresh parsley into the ground beef mixture, and allow it to sit while you prepare the couscous.
For the couscous, combine the 1 cup of dried couscous in a small pot with the 1 cup of boiling beef stock and the minced garlic.
Stir to combine, and cover with a tight-fitting lid for 6 minutes.
Remove the lid, gently fluff the couscous with a fork, and gently fold in the remaining fresh herbs, lemon zest, and lemon juice until combined.
Serve immediately in bowls, with some couscous, topped with seasoned ground beef and onions, topped with some homemade tzatziki sauce.