Add the olive oil to a large pot; then add the shallots, garlic and ginger. Saute over medium heat until translucent and soft, about 5 to 6 minutes, stirring often. Add the lemongrass and cook another 2 minutes. Add the lime juice and zest, sugar, tomatoes and coconut milk. Bring to a simmer and cook for 10 minutes. Use an immersion blender, food processor or blender to blend the bisque until smooth. Season to taste with salt and pepper.
For homemade garlic coconut croutons, blend the coconut oil, butter, garlic and salt together in a food processor or by hand until well combined. Put the baguette slices onto a baking sheet or pie pan and spread with the butter mixture. Bake in a 300°F oven for 5 to 7 minutes until golden brown.
Portion the bisque into bowls and top with croutons, fresh cilantro and Thai basil and a drizzle of olive oil. This dish pairs well with white or rosé wine.