In a medium-sized saucepan, heat the rhubarb, 1 ½ cups of strawberries and thyme sprigs over medium heat until they start to bubble and get syrupy.
Once they start to soften, remove the residual sprig and mash the fruit gently with a potato masher to a jammy, loose texture with some visible bits in it.
Add the lemon juice and honey to taste and transfer to a fridge-friendly container.
Mix in the chia seeds and allow to set in the fridge for at least two hours or overnight.
When ready to serve, add about 3 tbsp of ricotta to each piece of toast and top with a generous dollop of the chia jam.
Finish with the residual sliced strawberries and garnish with honey and thyme leaves, to taste, and a sprinkle of crushed pistachios.