Layout the salmon, asparagus, and cherry tomatoes onto a parchment paper lined sheet pan.
Grab a glass measuring cup and measure out the oil olive. Whisk in the the lemon juice, mustard, dill, oregano, and grated garlic. Add a healthy pinch of salt and fresh ground pepper, to your taste. Drizzle this over the salmon, asparagus, and tomatoes.
Place the salmon and veggies into the oven and let it roast for 15 minutes.
The Tzatziki and Serving
Add the Greek yogurt to a mixing bowl. Add the grated cucumber, garlic, lemon juice, fresh dill and chives. Mix that together until combined. Add kosher salt and fresh ground pepper, to your taste.
In the time that it takes to make the tzatziki, the Sheet Pan Salmon should be done. All that's left to do is serve the salmon, dollop the sauce, and enjoy!