Wash, dry and slice the shiitake mushrooms.
Heat the coconut oil in a large stockpot. When shimmering, add the shiitake mushrooms, stirring frequently, until the mushrooms are soft and just lightly browned. Set aside.
In the same stockpot, add the vegetable broth and water. Bring to a boil and add the lemongrass and fresh ginger. Bring to a boil and simmer for 20 minutes.
After simmering, add the vegan fish sauce, lime zest, sugar, red curry paste and coconut milk.
Add the lime juice one lime at a time and taste. Heat until warmed.
Add the mushrooms, shallot, broccolini and roma tomatoes. Heat until the broccolini becomes bright green.
Garnish with thai red chilies, sliced thin and fresh cilantro.