Because they use modernist ingredients, these amounts are given in metric by weight. For more information on how to measure modernist ingredients check out this article.
4g garlic powder
Preheat the water bath to 60.5°C (141°F). If you don't have a sous vide machine, the chicken breasts can be grilled or pan seared.
Combine the spices in a small bowl and mix well. Salt and pepper the chicken breasts then coat with the spice mixture. Seal them in a sous vide bag and place into the water bath. Cook for 2 to 4 hours. Remove from the sous vide pouches and pat dry. Cut the chicken into bite-sized cubes.
Heat a pan over medium to medium-high heat. Add oil and warm. Add the onion and cook until translucent, about 5 to 7 minutes. Add the garlic, ginger, and serrano pepper and cook for 2 minutes.
Add the tomato paste and garam masala and cook, stirring regularly, for 3 minutes. Add the crushed tomatoes, water, and honey then bring to a simmer for around 15 minutes. Salt and pepper to taste.
Add the agar, puree well, and bring to a boil for 3 to 5 minutes. Stir in the heavy cream then reduce the heat to just below a simmer and keep it there while dipping the chicken.
Stick a toothpick in a chicken cube then dip the chicken into the tikka masala coating. Set the cube on a plate, the coating should begin to harden quickly. Once the coating has set, you can re-dip it if you want a thicker coating. Repeat for the remaining chicken.
The dipped chicken can be re-heated in an oven set below 80°C (175°F).
Place a coated chicken cube on a dish, sprinkle on some cilantro and serve.