Place the tamarind pulp in a bowl and cover with 2 cups of warm water. Let it soak for about 20 minutes to soften.
Use your hands to break up the tamarind pulp and separate the seeds from the flesh. Strain the mixture through a fine-mesh sieve or cheesecloth, pressing to extract as much pulp and liquid as possible. Discard the seeds and fibers.
In a medium saucepan, combine the tamarind pulp, brown sugar, honey, grated ginger, ground allspice, ground cinnamon, ground cloves, cayenne pepper (if using), salt, and ground black pepper.
Bring the mixture to a boil over medium heat, stirring constantly until the sugar is dissolved.
Reduce the heat to low and let the sauce simmer for about 15-20 minutes, stirring occasionally, until it thickens to your desired consistency.
Remove the sauce from the heat and let it cool to room temperature. The sauce will continue to thicken as it cools.
Transfer the tambran sauce to a jar or airtight container and refrigerate until ready to use.
Use the tambran sauce as a condiment for grilled meats, seafood, or vegetables. It can also be used as a dip for fried foods or as a flavorful addition to sandwiches and wraps.
Enjoy your meal!