Heat oil in medium, heavy pot over medium-high heat. Add onion, garlic, cilantro and oregano. Cook, stirring occasionally, until onions soften, about 5 minutes. Add tomato paste; cook, stirring, until paste begins to caramelize, about 2 minutes more.
Add pigeon peas, chicken bouillon mixture, coconut milk and salt to pot; bring to boil. Stir in rice; return water to boil. Boil 1 minute. Reduce heat to medium. Simmer, without stirring, until water completely evaporates. Stir rice from bottom up. Reduce heat to lowest setting; cover pot. Cook, covered, until rice is completely tender, about 20 minutes.
Fluff rice with fork; serve.