Peel the pumpkin , remove the seeds and the fibrous pulp from the center. Cut the pumpkin pulp into small cubes and simmer for 10-15 minutes with orange juice in a saucepan, until the pumpkin is soft.
Transfer approximately one third of the pumpkin pulp in a large pot. Add the juice of the squeezed lemon, the zest and juice of one of the oranges. Peel remaining 2 oranges, taking care to remove the white skin. Add the orange quartiers to the punmpkin mix . Mix jam sugar and let sit for 1 hr, covered.
Puree the rest of pumpkin pulp with a handheld blender, add to the fruit mixture and cookover high heat, stirring. Once bubble start to form, cook for 4 more minutes, constantly stirring. Check if gelling point is reached. Add orange liqueur to taste, stir and fill jam into hot rinsed jars and seal.
Tip: free the pumpkin seeds from the fibers, lay on paper towel until dry. Roast dried seeds in a nonstick pan. Remove the white skin. A quick healthy snack for in between.
Variation 1: Slightly exotic. Replace orange juice with 250 ml coconut milk.
Variation 2: pumpkin and melon jam : Replace orange juice with 250 ml freshly squeezed melon juice.
Variation 3 : spicy pumpkin mousse
Cook 500 g pumpkin (just covered) with water in 10-15 minutes until soft and puree. Mix the puree with 250 g preserving sugar 2:1, 1 tsp freshly grated ginger, red chilli to taste and 2 tablespoons white wine vinegar, bring to a boil and cook 4 minutes once bubbly, stirring constantly. Chexk if gelling point is reached, fill in hot rinsed jars and seal.