In a large salad bowl, add the salmon, cucumber, red bell peppers, red onions, avocado and lettuce. Mix everything together until combined.
In a mason jar, pour the freshly squeezed lemon juice and olive oil. Add salt and pepper and whisk everything. Continue to whisk while streaming in the olive oil*.
Taste to check the seasoning and pour over the salad. Enjoy!
* This dressing stays good in the fridge in a sealed container for about 5 days.
* Preheat the oven to 400°F. Line a baking sheet with parchment paper or silicone mat. Place salmon on the baking sheet, skin-side down, season with salt and pepper and bake 10 to 12 minutes. Remove from the oven and let it cool down. Flake flesh and set aside.