To Make the Rice Paper Rolls: Preheat oven to 425F. Line a large baking pan with parchment paper. Evenly drizzle with half of the olive oil.
In a large skillet over medium high heat, add the tuna, grated carrots, onion, ginger, garlic, mushrooms, and bell pepper. Sauté for 8-10 minutes, until carrots are tender and there’s no more liquids in the pan. If needed, add 1 tbsp olive oil. Remove from heat to cool slightly.
Add cold water to a shallow rimmed dish. Working one at a time, place the rice paper roll in the water to soak 30 seconds. Place on a clean counter. Add 3-4 tbsp of the tuna mixture into the center. Let the rice paper sit for up to 1 minute on the counter, until soft enough roll but not dried out and sticking to the counter.
Roll up the rice paper roll like a burrito to seal in the tuna mixture. Place on the prepared pan. Repeat with remaining rice paper rolls.
Drizzle the rolls with the remaining olive oil and garnish with sesame seeds.
Bake for 20 minutes, then gently flip to bake another 15-20 minutes, until crispy on all sides.
To Make the Sauce: Combine the minced garlic, ginger, and olive oil in a saucepan over medium high heat. Sauté for 1-2 minutes. Stir in the flour.
Add the remaining ingredients and whisk until smooth. Let simmer for 4-5 minutes, until thickened. Enjoy with the crispy rice paper rolls!