Season your chicken breasts with salt and pepper, then gently simmer them in chicken broth until they turn no longer pink, about 15-20 minutes. Shred the chicken and set it aside, reserving the broth for later.

In a large skillet, melt the butter over medium heat. Add the finely diced onions, celery, and carrots, sautéing for about 5-6 minutes until they soften. Stir in the minced garlic and herbs, cooking for an additional minute until fragrant.

Sprinkle the flour over the sautéed vegetables, stirring to combine and cook for 1-2 minutes until it thickens slightly. Gradually whisk in the reserved chicken broth and half and half, stirring continuously to avoid lumps. Add the chicken bouillon cube and soy sauce, simmering until the gravy thickens.

Gently fold the shredded chicken and frozen peas into the gravy mixture. If you'd like a thicker consistency, gradually incorporate more broth until your desired texture is achieved.

Preheat your oven to 425°F (220°C). Spoon the chicken filling into a baking dish and top it generously with prepared biscuits. Bake for 15-18 minutes, until the biscuits are golden brown and puffed.

Remove the pot pie from the oven and let it cool slightly for about 5 minutes. Garnish with freshly chopped herbs if desired, and serve warm.