1/2 cup cold-pressed fruit or nut oil, hazelnut, olive, walnut, pistachio, etc.
Place the milk and heavy cream into a medium saucepan and set over medium heat. Bring the mixture just to a simmer, stirring occasionally, and remove from heat.
In a medium mixing bowl, whisk the egg yolks until they lighten in color. Gradually add the sugar and whisk to combine. Add the oil and whisk thoroughly. Temper the cream mixture into the egg mixture by whisking in small amounts, approximately 1 tablespoon at a time, until about a 1/3 of the cream mixture has been added. Pour in the remainder of the cream and stir to combine. Return the mixture to the saucepan and place over medium-low heat. Continue to cook, stirring frequently, until the mixture thickens slightly and reaches 170 to 175 degrees F, approximately 5 to 7 minutes. Strain the mixture through a fine mesh strainer into a container and place in the refrigerator uncovered. Allow to sit uncovered until it is cool enough not to form condensation on the lid. Cover and store for 4 hours, up to overnight, or until the temperature reaches 40 degrees or below.
Pour into an ice cream maker and process according to the manufacturer's directions, approximately 25 to 35 minutes. Serve as is for soft serve or freeze for another 3 to 4 hours to allow ice cream to harden. If freezing longer than 4 hours, remove from the freezer for 15 to 20 minutes before serving.