Porridge: In a saucepan, combine 1/2 cup water, coconut milk (or almond milk), steel cut oats, vanilla bean seeds, and black tea bags. Bring to a simmer over medium-high heat. Reduce heat to low, cover, and cook until oats are tender and creamy (20-30 minutes), stirring occasionally.
Steep Tea: Remove tea bags, squeezing them against the pan to release steeped tea into the porridge. Discard tea bags. Remove vanilla bean pod.
Sweeten & Adjust: Stir in honey. Add more milk if needed to reach desired creamy consistency.
Acai Ripple: While oats cook, blend frozen berries, acai powder, maple syrup, and 2 tablespoons of water until smooth.
Pistachio Cream: Blend full-fat canned coconut milk and pistachios until completely smooth (about 5 minutes), scraping down sides as needed.
Assemble: Divide warm porridge into two bowls. Swirl in the acai sauce. Drizzle generously with pistachio cream and top with fresh berries, chopped pistachios, and a final drizzle of honey.